The Correlation Between SDC-4 And Left Ventricular Diastolic Dysfunction With Hypertension

Left ventricular diastolic dysfunction could be the heart failure preserved ejection fraction(HFpEF) without intervention. Recently the epidemiologic studies indicated that the incidence of the heart failure preserved ejection fraction was approximately 1/3 in the heart failure. Different from the heart failure reduced ejection fraction(HFr EF), heart failure preserved ejection fraction(HFpEF) has higher emergency admission risk. In the natural course of heart disease caused by hypertension, diastolic dysfunction occurs early than systolic dysfunction. Hypertensive heart disease is one of the important promoter to the left ventricular diastolic dysfunction. Before myocardial hypertrophy formed, the synthesis of myocardial collagen has increased obviously and left ventricular diastolic function has declined. The inflammatory factor plays a significant role in the process of myocardial fibrosis. Syndecan-4 is a member of inflammatory factor. To discuss the performance of Syndecan-4 in the left ventricular diastolic dysfunction can deepen understanding of the influence of the inflammatory factor to the left ventricular diastolic dysfunction and provide a new strategy to intervene the left ventricular diastolic dysfunction.Syndecan 4, belonging to the surface proteoglycan family, is a co-receptor for the growth factor. It can mediate numerous cellular processes, including inflammatory response. Syndecan 4 level is up-regulated in hypoxic fibroblasts, endothelial cells and cardiomyocytes, suggesting that it plays a role in response to cardiovascular injury. However, the study of Syndecan 4 in the cardiovascular disease is more focused on atherosclerosis and myocardial infarction now. As for the left ventricular diastolic dysfunction, further basic and clinical researches are needed.Based on the above findings, the study is to analyze the correlation between Syndecan 4 and the left ventricular diastolic dysfunction. [Objectives]Investigate the expression of serum Syndecan 4 in the process of two kidney-two clip(2k2c) rat model, banding the serum BNP, changes of myocardial collagen and echocardiography, and analyze the correlation between Syndecan 4 and left ventricular diastolic dysfunction with hypertension. [Methods]41 healthy Sprague-Dawley male rats, 80-100 g in weight, ranging in age from 60 to 90 days, 36 of them were divided into a 2k2 k hypertension group(21) and a sham-operated group(15) randomly. Two kidney-two clip(2k2c) rat model were formed in the 2k2 c hypertension group. The sham-operated group were operated the same way exclude renal artery clamps. On the basis of the different time after the operation, the two groups were divided into 3 subgroup separately at random, 7 in 2k2 c hypertension subgroup and 5 in sham-operated subgroup. They were kept till 4th week, 8th week and 12 th week respectively. Blood pressure, weight, echocardiography, HE stain, Masson stain, ELISA of BNP and SDC-4 were recorded at the end of feeding time. The data of last 5 rats were picked before the operation. In the end, statistical software was used for the data analysis. [Results]Other from the sham-operated group, the blood pressure of rats in the 2k2 c hypertension group increased, as well as the thickness of left ventricular, LVMI, BNP and SDC-4. The diastolic function decreased reversely. Hematoxylin-Eosin stain and Masson’s trichrome stain revealed the 2k2 c hypertension group showing obvious hyperplasia of fibrotic tissue compared with those in the sham-operated group(P<0.05). Pearson analysis found a positive correlation between SDC-4 and E/E’, Tei meanwhile(<0.01). [Conclusions] Syndecan-4, one of the inflammatory factors,were active in the left ventricular diastolic dysfunction and may contributes to the formation of myocardial fibrosis, as well as the left ventricular diastolic dysfunction through its inflammatory process.This paper suggested that to intervene in SDC-4 may be a effective treatment measures for the left ventricular diastolic dysfunction.