Abstract:

Objective  To investigate the expression pattern of a new immune negative regulator，TIPE2（tumor necrosis factor-α induced protein 8 like 2）and the inflammatory factors of atherosclerosis plaque of ApoE-knockout mice (ApoE-/- mice) and to analyze the relationship between them. Methods ApoE-/- mice were used to establish atherosclerosis models and wild type C57 rats served as the controls. The formation of atherosclerosis plaque was observed under microscopy after HE and oil red O staining and then the expression of TIPE2 and inflammatory factors were determined by reverse-transcript polymerase chain reaction. After quantization, their linear correlation was analyzed. ResultsWhen the 8 week-old ApoE-/- mice were fed with high-fat until 16 or 24 weeks old， atherosclerosis plaque was found in the arteries, while this did not occur in the control group. Expression of TIPE2 at the aorta of ApoE-/- mice was significantly higher at no plaque stage (8 weeks), early stage (16 weeks) and middle-advanced stage (24 weeks) than that of the control group. Expression of IL-6 was not significantly different from that of the control group in all processes of atherosclerosis. When there was no plaque at the aorta,  expression of IL-12p40, TGF-β and TNF-α were significantly higher(P<0.05). During the early stage the expression of IL-12p40 decreased and there was no differencebetween the ApoE-/- and the C57 mice, while the expressions of TGF-β and TNF-α were significantly increased (P<0.05). With the development of plaque, expression of only TGF-β was increased (P<0.05) at the middle-advanced stage. Further analysis showed that expression of TIPE2 was positively correlated with that of TNF-α but was not relevant to expression of IL-6, IL-12p40 and TGF-β. Conclusion TIPE2 expression at the aorta of the ApoE-/- mice is significantly higher than that of the control group and is positively correlated with that of TNF-α, indicating the role of TIPE2 in the origin of atherosclerosis.

Key words: Gene, TIPE2; Chemokines; Aterosclerosis; Mice, Knockout