Shedding of Syndecan-4 contributes to inflammation in the left atrial tissue in patients with valvular atrial fibrillation / 医学研究生学报

ABSTRACT

Objective Inflammation plays a critical role in the presence , development and maintenance of atrial fibrillation ( AF) , but it remains unclear what factors induce inflammation in AF patients , especially in those with valvular heart disease ( VHD) . The aim of this paper was to investigate the role of the shedding of Syndecan -4 in left atrial inflammation in patients with valvular atrial fibrillation. Methods Sixty VHD patients scheduled for valvuloplasty or valve replacement surgery were divided into three groups of equal numbersinus rhythm (SR), paroxysmal atrial fibrillation (PaAF), and persistent atrial fibrillation (PeAF).Another 10 pa-tients with congenital heart disease but no valve damage and atrial fibrillation were included in a control group .Baseline clinical data were recorded and tissues were obtained from the left atrial appendage during operation .The expressions of iNOS , HMGB1, and Syn-decan-4 in the left atrium were detected by Western blot , and the pathological changes of the left atrial tissue observed by HE staining . Results Western blot analysis was performed to detect expression levels of proteins .The iNOS level was significantly higher in pa-tients from the paroxysmal AF group (1.61 ±0.10) and persistent AF group (1.67 ±0.08) than those from sinus group (1.06 ± 0.11) and control group (1.02 ±0.12), as was the protein level of HMGB1 (0.63 ±0.05, 0.95 ±0.10, 0.45 ±0.07 and 0.46 ± 0.06 in paroxysmal AF group, persistent AF group, sinus group and controlgroup respectively ).Inflammatory cell infiltration in-creased, while syndecan 4 was down-regulated in AF groups.All these comparisons were significant (P<0.05). Conclusion The decreased expression of Syndecan-4 and enhanced inflammatory response in the left atrial tissue indicate that the shedding of Synde-can-4 may play a role in the presence and development of inflamma-tion in the left atrium .