Objective To search for the key microRNAs (miRNAs) involved in myocardial fibrosis in hypertrophic cardiomyopathy, and to further explore the mechanisms involved in the regulation of myocardial fibrosis. MethodsForty-two patients with hypertrophic cardiomyopathy diagnosed and treated surgically in West China Hospital of Sichuan University from January 2014 to June 2018 were selected, including 29 males and 13 females, with a median age of 46 (15-69) years. In the myocardial tissue of patients with hypertrophic cardiomyopathy with different degrees of fibrosis, miRNAs with significantly different expression were screened and further verified at the cellular level. By regulating the expression of the target miRNAs, the expressions of fibrosis-related proteins and target genes were detected respectively. Finally, the target-binding relationship was verified by dual-luciferase reporter gene detection. ResultsmiR-484 was up-regulated in severely fibrotic myocardial tissue and activated cardiac fibroblasts. After cardiac fibroblasts were activated by TGF-β1, the expression of miR-484 was significantly up-regulated, the expression of fibrosis-related proteins (CollagenⅠ, α-SMA) increased, and the expression of the target gene HIPK1 decreased (P<0.05). After inhibiting the expression of miR-484 by transfection of miR-484 antagomir, the expression of fibrosis-related proteins decreased, while expression of HIPK1 was up-regulated (P<0.05). The detection of dual luciferase reporter gene showed that the luciferase activity of the transfected WT-miRNA-484 mimics group was lower than that of the control group (P<0.05). ConclusionmiR-484 is a pro-fibrotic miRNA that participates in the process of myocardial fibrosis by negatively regulating the expression of HIPK1. It can be used as a regulatory target to provide a therapeutic strategy for myocardial fibrosis.
ObjectiveTo compare the superiority of total arterial revascularization in patients with coronary artery disease (CAD) complicated with left ventricular dysfunction. MethodsThis retrospective study included the patients who were diagnosed with CAD and the left ventricular ejection fraction (LVEF) of ≤40% and underwent coronary artery bypass grafting (CABG) at our hospital from January 2016 to July 2019. The patients were divided into two groups according to the different types of bypass vessels: a total arterial revascularization group (TAR group) and a conventional group (a CON group). The clinical data were compared between the two groups to explore the incidence of important complications and evaluate the safety of total arterial revascularization and its protective effect on cardiac function. Results Finally 75 patients were enrolled including 52 males and 23 females with a mean age of 61.58±7.93 years. There were 35 patients in the TAR group and 40 patients in the CON group. The operation time and the drainage volume at 24 hours after operation in the TAR group were longer or more than those in the CON group (P<0.05), but there was no statistical difference in hospital stay, postoperative complications (such as respiratory failure, mediastinal infection, renal failure), intra-aortic balloon pump or extracorporeal membrane oxygenation use rate (P>0.05). After 2 years of follow-up, compared with the CON group, the cardiac function of the TAR group was significantly improved, the LVEF was higher, the left ventricular end diastolic diameter was reduced, and the graft stenosis rate was lower (all P<0.05). Conclusion Total arterial revascularization is a safe and feasible surgical method, which is helpful to improve the cardiac function and improve the quality of life.