MiRNA-134 Promotes Atherosclerosis Development Via The ANGPTL4LPL Pathway In ApoE Knockout Mice

Atherosclerosis is the most common cause of cardiovascular diseases.Recent studies showed that mi R-134 may promotes atherosclerosis.Angiopoietin-like 4(ANGPTL4)and lipid lipoprotein(LPL)are closely associated with lipid accumulation and inflammatory response.However,the influence of mi R-134 on atherosclerosis remains to be determined.These findings suggested that mi R-134 accelerates atherogenesis by promoting lipid accumulation and proinflammatory cytokine secretion via the ANGPTL4/LPL pathway.Therefore,targeting mi R-134 may offer a promising strategy for the prevention and treatment of atherosclerotic cardiovascular disease.Objective: To observe the mechanism of mi R-134 on lipid accumulation and inflammation response of apo E knockout mice.Methods: These mice were randomly divided into four groups: mi R-134 agomir negative control(AG-NC),mi R-134 agomir(AG),mi R-134 antagomir negative control(AN-NC)and mi R-134 antagomir(AN).Each group included 10 animals and started the high-fat/high-cholesterolWestern diet for 12 weeks.HE staining were used to detect the artery atherosclerosis lesions;Oil red O staining were used to evaluate aortic and lipid deposition in the aortic sinus;ANGPTL4 and LPL m RNA level of abdominal cavity macrophage and aorta tissue on apo E knockout mice were detected by fluorescence quantitative PCR;Western blotting method was used to detect ANGPTL4 and LPL protein expression of apo E knockout mice;We used Immune coprecipitation method to evaluate the combination of LPL and LRP1 situation on abdominal cavity macrophage,and ELISA method to detect the pro-inflammatory factors(TNF-?,MCP-1,IL-6 and IL-1?)secretion of serum and peritoneal macrophages;High-performance liquid chromatography assays(HPLC)were used to detected lipid levels of serum and peritoneal macrophages.Results: The oil red O staining and HE staining methods were used to evaluate aortic sinus,and we found that the lesion area and aortic sinus of apo E knockout mice were significantly increased when transfecting with mi R-134 agomir.While mi R-134 antagomir had an opposite effects,which suggesting that mi R-134 has promoting effect on the formation of AS.The m RNA and protein expression of ANGPTL4 and LPL were detected by fluorescence quantitative PCR and Western blotting,respectively.These results showed that mi R-134 decreased ANGPTL4 expression but elevates LPL expression and activity in peritoneal macrophages and aorta of apo E knockout mice.Immunoprecipitationmethod was used to detect the formation of LDL / LRP1 complex.We found that mi R-134 agomir promotes the LPL/LRP1 complex formation in peritoneal macrophages of apo E knockout mice.Moreover,the levels of plasma total cholesterol(TC)and low density lipoprotein(LDL-C)were significantly increased,while the levels of triglyceride(TG)and high density lipoprotein(HDL-C)were greatly decreased in the peritoneal macrophages and serum.Finally,ELISA method was used to evaluate the secretion of proinflammatory cytokine,such as TNF-?,MCP-1,IL-6 and IL-1?.These results suggested that mi R-134 agomir markedly promoted the proinflammatory cytokine secretion,however,an opposite effect was observed in response to mi R-134 antagomir.Conclusion: Mi R-134 increases the LPL expression and activity by inhibiting ANGPTL4 expression,promotes lipid accumulation and proinflammatory response,eventually accelerates the atherosclerosis formation of apo E knockout mice.