An experimental study on the relation between coronary artery calcification and calcium deposition in cardiomyocytes

Wang Yue; Zhou Yuan; Shi Fengru; Zhao Lei; Wen Songnan; Qiao Yan; Lyu Qiang; Bai Rong; Yu Ronghui

doi:10.3760/j.issn.1673-4777.2019.10.002

Abstract：Objective To investigate the relation between coronary artery calcification and calcium deposition in cardiomyocytes. Methods From January to June 2017, 8 patients undergoing cardiac valve replacement+atrial fibrillation ablation+left atrial appendectomy in Beijing Anzhen Hospital, Capital Medical University were recruited. Dual-source cardiac CT scanning was performed to calculate coronary calcium score before surgery. Left atrial appendage was removed. Calcium deposition in cardiomyocytes was observed by von Kossa staining and alizarin red staining. Alkaline phosphatase( ALP) activity and calcium content in myocardial tissue were tested by the kits. Expressions of osteogenesis associated protein core binding factor ( Runx2 ) , osteopontin and β-catenin were detected by western blotting. Osteopontin, endothelin and ghrelin mRNA expressions were detected by reverse transcription-polymerase chain reaction. Relations between coronary calcium score and above indicators were analyzed by single factor linear regression and logistic regression. Results Coronary artery calcification scores of 8 patients were 0, 0, 0, 6, 31, 50, 112 and 417, respectively. Logistic regression analysis showed no correlation between coronary artery calcification score and myocardial calcification ( von Kossa staining: odds ratio=0. 984, P=0. 479;alizarin red staining:odds ratio=0. 983, P=0. 356). Linear regression analysis showed no correlation of coronary artery calcification score with protein expressions of myocardial calcium content, ALP activity, osteopontin andβ-catenin protein expression, mRNA expressions of osteopontin, endothelin and ghrelin ( normalized regression coefficient= -0. 221, 0. 558, -0. 523, -0. 562, 0. 129, 0. 021, 0. 020; P =0. 595, 0. 154, 0. 186, 0. 154, 0. 751, 0. 971, 0. 956); there was a negative correlation between coronary artery calcification score and Runx2 protein expression(standardized regression coefficient= -0. 752, P=0. 032). Conclusions There is no correlation between coronary artery calcification and calcium deposition in cardiomyocytes.