The Effect Of Danlou Tablets And Its Components On Ventricular Remodeling After Acute Coronary Syndrome

Part1The effect of Danlou tablets on ventricular remodeling in patients with acute coronary syndromeObjective:Evaluate the effect of Danlou tablets on ventricular remodeling in patients with acute coronary syndrome after revascularization.Methods:The study is a randomized parallel controlled clinical trial with three-month clinical follow-up. From Jun.2012to Dec.2013,88patients with acute coronary syndrome after revascularization, from Guangdong Provincial Hospital of TCM and Wuyi Hospital of TCM were enrolled and randomly grouped. The control group (n=44) received standard therapy according to the guideline of modern medicine, the treatment group (n=44) received standard therapy combined with Danlou tablets. Clinic follow-up was performed to evaluate the cardiac function, including echocardiography measurement (cardiac output, left ventricular end diastolic diameter, left ventricular end systolic diameter, stroke volume as well as left ventricular ejection fraction), NYHA cardiac functional classification and quality of life assessment.Results:There are83(94.32%) patients accomplished the follow-up.5case (5.68%) was lost (2case in treatment group v. s.3case in control group). The average follow-up time was91.2±5.1days. The distributions of the demographic and clinical characteristics between control group and the treatment group were well balanced and homogeneous. At the90-day follow-up, a significant increase in cardiac fuction measured by echocardiography was observed in both group, but the Danlou tablets demonstrated a significantly greater reduction in the level of LEVDD and LEVSD than the placebo group. Treatment with Danlou tablets also demonstrated superior performance in comparition to the placebo with respect to the New York Heart association functional classification and quality of life. In details, patients treated with Danlou tablets were demonstrated improved total scores of quality of life, as well as in dimension of clinical symptoms, mental health and social support (p<0.05). However there was no statistically difference in terms of active limitation between two groups.Conclusion:On the background of standard treatment, Danlou tablets futher reduced cardiac remolding which was reflected by the levels of LEVDD and LEVSD. In addition, Danlou tablets can improve patients’New York Heart association functional classification and quality of life. Together, our data suggest that danlou could be used in combination therapy for acute coronary syndrome. Part2The effect of Danlou tablets and its components on different extracellular matrix proteinsObjective:The extracellular matrix remolding is the pathophysiological basis of ventricular remodeling. The cardiac fibroblasts play important role in the deposition of extracellular matrix and are the mainly responsable cell in cardiac remolding. The property of proliferation and changes of functionality are determinated the changes of myocardial structure. In clinical study, we reported that Danlou tablets alleviated the maladaptive left ventricular hypertrophy in patients following ACS. However, there is an absence in the literature of detailed studies on the effect of this medicine on peculiar changes in the extracellular matrix produced by cultured human cardiac fibroblasts. Our present studies investigated the mechanism by which Danlou tablets and its components produce these cardiac beneficial effects, specifically whether and how it differentially modulates the major components of the extracellular matrix.Methods:Isoproterenol was used to induce myocardium infarction in rats. HE staining and immunohistochemistry test were performed to observe the histomorphology. The degree of myocardial fibrosis as assessed by evaluation of sirius red stained heart sections. The trypsined digestion and adhesion method were used in primary culture of cardiac fibroblasts. Cardiac fibroblasts were identified by positive staining for vimentin via immunohistochemistry. Cellular proliferation rates were assessed by3H-thymidine incorporation, DNA content and Ki-67antigen expression. Total RNA from cardiac fibroblasts was analyzed for the steady-state levels of mRNAs encoding collagen Ⅰ, Ⅲ, fibronectin and elastin by qRT-PCR. Western Blot analysis was preformed to assess the level of collagen Ⅰ, Ⅲ, fibronectin and elastin. The stability of mRNA was determined in fibroblasts cultures simultaneously incubated with DRB. qRT-PCR, Western Blot analysis as well as immunofluorescence staining were preformed to assess the signal pathway that effect the production of collagen or elastin.Results:Danlou tablets can decrease the ventricular remolding and collagen fibers deposition in rats after myocardium infarction. We found that treatment with the component of Danlou tablets (tanshinone IIA) not only caused a significant inhibition of collagen or fibronectin synthesis and deposition, but also enhanced production of new elastic fibers in cultures of human cardiac fibroblasts in the dose dependent manner. RNA stability analysis showed that tanshinone IIA significantly decreases the stability of mRNAs encoding collagen I and fibronectin, while increases the stability of elastin mRNA. This may partly explain the mechanism underlying this phytoestrogen differentially modulates the deposition of extracellular matrix. We further demonstrated that the anti-fibrotic effect of tanshinone IIA occurs after down-regulating production of TGFβ1, activation of TGFβR1, Smad2and ERK1/2MARK associated with the nuclear translocation of Smad4. We further demonstrated that the pro-elastogenic effect of this phytoestrogen occurs after selective activation of G protein-coupled estrogen receptor, but not classic oestrogen receptor, which further triggers the downstream PKA/CREB pathway contributing to elastin gene transcription.Conclusion:Animal study demonstrated that Danlou tabelts reduces the process of cardiac remolding in rats that would allow for the best possible resiliency of the post-infarct scars and the optimal cardiac function. Results of study in vitro for the first time demonstrated that treatment of cultured human cardiac fibroblasts with the component of Danlou tablets (tanshinone IIA) lead to a remarkable decrease in the net deposition of collagen fibers associated with a significant increase in the synthesis of tropoelastin and a net deposition of elastic fibers. Importantly, we present experimental data indicating that the elastogenic effect of tanshinone IIA is not mediated through the classic oestrogen receptor, but occurs after the exclusive stimulation of the G protein-coupled estrogen receptor that triggers the PKA-dependent phosphorylation of CREB. We also demonstrate that tanshinone IIA down-regulates activation of classic or non-classic TGFβ1pathway. In summary, our data support the hypothesis that tanshinone IIA differentially modulates the deposition of major extracellular matrix through specific signaling pathway may counteract pathological remolding. Since the inhibition of collagen deposition prevents stiffening of injured myocardium and the simultaneous deposition of elastin provides it with an extra resiliency and ultimately reduces the chance for the post-infarct heart failure.