Abstract:

Objective   To observe the expression of sirtuin 1(SIRT1)，one of the class III histone deacetylases in atrial tissue in patients with atrial fibrillation (AF) and clear the relationship between the expression of SIRT1 and atrial fibrosis.  Methods   38 patients with rheumatic heart disease who underwent cardiac surgery were divided into two groups: the AF group (atrial fibrillation, n=25) and the SR group (sinus rhythm, n=13). The right atrial appendage tissue was obtained during the heart valvular surgery. The expression of SIRT1 mRNA in atrial tissue was detected by realtime quantitative PCR and the expression of SIRT1 protein was detected by immunohistochemical assay. The atrial structure was measured by the transthoracic echocardiography and the extent of atrial fibrosis was identified by masson staining. Results   Compared with that of the SR group, the expression of SIRT1 mRNA in atrial tissue was significantly higher in the AF group (P<0.05), the expression of SIRT1 protein was also significantly higher in the AF group (P<0.05). Spearman correlation indicated that the expression of SIRT1 had no correlation with the dimension of atrium(left atrium： r=0.198, r=0.047， right atrium： r=0.027, r=0.096， P>0.05) in the AF group. Spearman correlation indicated that the expression of SIRT1 had significantly negative correlation with the amount of collagen volume fraction in the AF group(r=-0.643，  r=-0.721， P＜0.05). Conclusion   The expression of SIRT1  is  increased in patients with AF, which indicates SIRT1 may affect AF by means of inhibiting the process of atrial fibrosis.

Key words: SIRT1; Atrial fibrillation; Atrial fibrosis; Rheumatic heart disease; Atrial tissue