长链非编码RNA-DCRF通过调控心肌细胞自噬和凋亡参与糖尿病性心肌病的发病机制

Cardiomyocyte autophagy and apoptosis are important molecular mechanisms of diabetic cardiomyopathy (DCM). In the previous study, we found that the expression of lncRNA-DCRF was significantly upregulated in the myocardium of DCM rats. Cell experiments confirmed that DCRF was associated with autophagy and apoptosis in cardiomyocytes. Therefore, we hypothesize that high glucose may regulate cardiomyocyte autophagy and apoptosis by increasing DCRF expression, which consequently leads to the progression of DCM . We will perform in vivo and in vitro experiments in this study. Firstly, we establish the diabetic animal model, introduce the DCRF-shRNA lentiviral vector into the myocardium, and investigate the effects of DCRF on the cardiac structure and function. Secondly, we culture neonatal rat cardiomyocytes and carry out luciferase reporter gene, ChIP and RIP experiments to verify: (1) high glucose regulates cardiomyocyte autophagy and apoptosis through the FOXD3/DCRF pathway; (2) DCRF silences the expression of DIRAS3 by epigenetic mechanism, thereby reducing cardiomyocyte autophagy; (3) DCRF functions as a competing endogenous RNA to upregulate p38 by sponging miR-24, thereby inducing cardiomyocyte apoptosis. The present study will provide new ideas and targets for the clinical treatment of DCM.

心肌细胞自噬与凋亡是糖尿病性心肌病（DCM）的重要分子机制。本课题组前期研究发现，lncRNA-DCRF在DCM大鼠心肌组织中表达显著上调，细胞学实验证实DCRF与心肌细胞自噬和凋亡相关。因此，我们推测高糖可能通过DCRF调控心肌细胞自噬与凋亡，从而促进DCM的发生发展。本研究分为体内实验与体外实验：（1）建立糖尿病动物模型，将DCRF-shRNA慢病毒载体导入老鼠心肌组织内，然后运用超声心动图、组织病理学等方法揭示敲减DCRF对糖尿病老鼠心脏结构与功能的影响；（2）原代培养乳鼠心肌细胞，运用荧光素酶报告基因、ChIP、RIP等方法验证：①高糖通过FOXD3/DCRF通路调控心肌细胞自噬与凋亡；②DCRF通过表观遗传学机制沉默DIRAS3表达，从而减少心肌细胞自噬；③DCRF通过竞争性抑制miR-24上调p38表达，从而促进心肌细胞凋亡。本研究为今后临床上DCM的治疗提供了新的思路和靶点。

糖尿病性心肌病（DCM）是糖尿病重要的心血管并发症，而心肌细胞自噬是DCM的关键分子机制。本课题组前期研究发现，长链非编码RNA-DCRF在DCM小鼠心肌组织中表达显著上调，细胞学实验证实DCRF与心肌细胞自噬相关。因此，我们推测高糖可能通过调控DCRF表达诱导心肌细胞自噬，从而促进DCM的进展。本研究分为体内实验与体外实验：1）建立DCM小鼠模型，运用超声心动图、组织病理学等方法揭示敲减DCRF对小鼠心脏结构与功能的影响；2）原代培养心肌细胞，运用多种分子生物学方法验证：①高糖通过调控FOXD3/DCRF通路诱导心肌细胞自噬；②DCRF通过竞争性抑制miR-551b-5p上调PCDH17表达，从而促进心肌细胞自噬。本研究初步阐明DCRF在DCM发病机制中的作用，为今后临床上DCM的治疗提供新的思路和靶点。