Effect Of Hydrogen Sulfide On Balloon Injury-induced Atherosclerotic Plaque And IL-10 Expression In Rabbit Carotid Arteries

Objective This study aims to investigate the effect of hydrogen sulfide(H2S), a new gaseous signaling molecule, on balloon injury-induced atherosclerotic plaque and Interleukin -10 (IL-10) protein and mRNA expression in the carotid arteries of rabbits fed with high fat diet and to observe the effect and mechanism of H2S in atherosclerotic disease.Methods Totally 32 male New Zealand rabbits were randomly divided into 4 groups: sham-operation group, model group, NaHS group and PPG group ,with 8 rabbits in each group. Rabbits in the sham-operation group were fed with normal diet, while those in the rest three groups were fed with high fat diet. One week later, the atherosclerosis model was established through adopting the improved Clowes carotid artery intimal balloon injury. After the operation, normal saline 1 ml/(kg·d) was injected to the Sham group and Model group ,and NaHS 20μmol/(kg·d) was given to the NaHs group, and PPG 20 mg(kg.d) was injected to PPG group, with this process continuing for 8 weeks. All the rabbits were weighted before the killing and operation. The H2S content and plasma lipid levels were measured. The vascular pathology and the thickness ratio of blood vessel intima at the injured spot were observed by HE staining. Moreover, through immunohistochemistry and Western blotting the expression of IL-10 plaques was investigated. And the IL-10 mRNA expression of carotid artery plaque was detected through RT-PCR methods.Results In each group the weight of rabbits increased significantly compared with that before the experiment. The TC, TG and LDL-C in each group increased remarkably while the HDL-C greatly decreased.The difference was statistically significant (P <0.01), but the difference in each group at the same period showed no statistical significance (P>0.05). In comparison with the sham-operation group, H2S concentration of plasma in the model group significantly decreased (P<0.01) and the tunica intima was obviously thickened (P<0.01), while changes in expression of IL-10 protein and gene showed no statistic significance (P>0.05). Compared with the model group, H2S concentration of serum in NaHS group remarkably increased (P<0.01), while the thickening of tunica intima was suppressed (P<0.01) and the expression of IL-10 protein and gene increased significantly (P<0.05). In PPG group, H2S concentration of serum became lower (P<0.05) and the area of injured tunica intima became thicker (P<0.01) than those in the sham-operation group and the model group, while the expression of IL-10 protein and gene showed significant decrease (P<0.05). Conclusion1. Balloon injury can significantly inhibit the production of H2S, leading to the formation of distinct AS plaques in the short term.2. The effect of H2S on the inhibition of atherosclerotic plaque formation is likely to be incented by the rising of the IL-10 expression in atherosclerotic plaque.