The Effect Of Resistin-like Molecule β On The Vulnerability Of Atherosclerotic Plaque In ApoE-/- Mice

Objective To explore the effect of Resistin-like molecule P (RELMβ) on the vulnerability of atherosclerotic plaque in ApoE-/- mice. Method 60 male ApoE-/-mice (8 weeks old) were fed with a high-fat diet and placed a constrictive silastic tube to induce the vulnerable plaque. At 8 weeks after surgery, all the mice were divided into three groups (n=20 per group):control, si-NC and si-RELMβ. At the end of 14 weeks, apoE-/- mice were euthanized to collect the right common carotid arteries and blood from the left ventricle. Blood samples were used to detect the content of total cholesterol, triglycerides, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol. Western blot analysis detect the protein expression levels of RELMβ in the three groups. Collagen Sirius red staining was performed to detect collagen and oil-red O staining was used to detect lipoid deposition in plaques. Immunohistochemical analysis was used to detect the content of macrophages, smooth muscle cells (SMCs), IL-1β and IL-6. Results The three groups of ApoE-/-mice had no significant difference in body weight and the lip id levels. Compared with the control group, the protein expression of RELMβ was significantly decreased in si-RELMβ group, while no significant change in si-NC group. Compared with the control group, the content of collagen and SMCs was significantly increased, while the content of lip id and macrophages, the expression of IL-1β and IL-6 and the vulnerable index were significantly decreased in the si-RELMβ group. Conclusion RELMβ could increase atherosclerotic plaque instability, whose mechanism was partly through promoting the expression ofIL-1β and IL-6.