GW24-e1856 Mechanical stretch induced cardiac fibroblasts proliferation, transdifferentiation and apoptosis is mediated by calcineurin pathway. (1st October 2013)

• Record Type: Journal Article
• Authors: Mingqiang, Fu; Jingmin, Zhou; Hongmin, Zhu; Jianquan, Liao; Kun, Jiang; Lingti, Zhu; Yunzeng, Zou; Junbo, Ge
• Is Part Of: Heart. Volume 99(2013)Supplement 3
• Page Start: A34
• Page End: A35
• Publication Date: 2013-10-01
• Subjects: Heart -- Diseases -- Treatment -- Periodicals; Cardiology -- Periodicals; 616.12
• DOI: 10.1136/heartjnl-2013-304613.90
• Languages: English
• ISSNs: 1355-6037

Abstract

Abstract : Objectives: To investigate if calcineurin pathway is involved in cardiac fibroblasts proliferation, transdifferentiation and apoptosis induced by mechanical stretch. Methods: Primary cardiac fibroblasts from 1- to 2-day-old Sprague-Dawley rats were isolated by trypsinization and purified by differential anchoring velocity technology. The cultured cells of passage 2-3 were divided into: control group, mechanical stretch group (MS group), calcineurin siRNA + mechanical stretch group (CaN-siRNA + MS group), FK506 + mechanical stretch group (FK506 + MS group), calcineurin overexpression + mechanical stretch group (CaN-overex + MS group). Calcineurin and downstream NFAT3 expressions were determined by western blot. Cardiac fibroblasts proliferation was determined by cell counting kit-8 and detection of proliferating cell nuclear antigen (PCNA), cell transdifferentiation was measured by alpha-smooth muscle actin (alpha-SMA) through western blot and apoptosis by Bax/Bcl-2. Results: Mechanical stretch promoted cardiac fibroblasts proliferation, as well as upregulation of alpha-SMA and increased Bax/Bcl-2 ratio, overexpression of calcineurin could promote more cardiac fibroblasts adverse remodelling similar to those induced by mechanical stretch. Pretreatment with calcineurin-siRNA lentivirus significantly attenuated cardiac fibroblasts proliferation, transdifferentiation and apoptosis when later stimulated by mechanical stretch, whereas pretreatment with FK506, a calcineurin inhibitor, only moderately inhibited cardiac fibroblasts proliferation and apoptosis with no obvious effect on cell transdifferentiation. Conclusions: This study demonstrates that mechanical stretch promoted cardiac fibroblasts proliferation, transdifferentiation and apoptosis via activating calcineurin/NFAT3, thus abolishing the calcineurin pathway might be beneficial for reversing myocardial fibrosis.