Protective effect of Shuyu Yiban decoction on atherosclerosis in rats induced by chronic unpredictable mild stress

Abstract

Shuyu Yiban decoction(SYYB) has significant effect in treating the patients with coronary heart disease combined with chronic psychological stress. In this study, in order to observe the effects of SYYB on early formation of atherosclerosis(As) and inflammation response induced by chronic psychological stress, high-fat diet+intraperitoneal injections of Vitamin D3 were given to establish As early lesion models, and based on these models, chronic unpredictable mild stress(CUMS) was used to observe whether the chronic psychological stress could increase coronary atherosclerotic lesions investigate the intervention effect of SYYB(6.6, 13.2, 26.4 mg•kg⁻¹). The tail suspension test and novelty-feeding test were adopted to detectadrenocortico-tropic hormone(ACTH), cortisol(Cor) andnoradrenaline(NE) in serum and weigh thymus and adrenal gland, in order to assess the effects of SYYB on CUMS model rats. The pathological changes of vascular tissues in aortic arch were observed by using hematoxylin and eosin(HE) staining, and then the levels of triglycerides(TG), total cholesterol(TC) and high density lipoprotein(HDL-C) in serum were determined to assess effects of SYYB on As lesions. The effects of SYYB on the inflammatory response in As rats were assessed by detecting high-sensitivity C-reactive protein(hsCRP), interleukin-1β(IL-1β) and interleukin-6(IL-6) in serum. The results showed that as compared with the blank control group, TC and TG levels in As group were increased while HDL-C was markedly decreased; furthermore, the aortic wall was thickened in HE staining. Meanwhile, foam cells were formed, and the behavioral assessment and serum stress hormone test showed that there was a chronic stress response, indicating successful establishment of As+CUMS models in this study. The experiment demonstrated that SYYB could lower the levels of serum TC and TG, reduce foam cells, calcification and inflammatory cells infiltration. Moreover, SYYB could obviously lower levels of ACTH, Cor and NE and the As related inflammatory indicatorhs-CRP, IL-1β and IL-6 in serum.These results indicated that SYYB had protective effect on chronic psychological stress induced in As rats, and the mechanism was associated with balancing the neuroendocrine-immune network system and regulating inflammation response.