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               ·314 ·                          南   京 医 科       大 学      学 报                        2024年3月


              related gene,atrial natriuretic peptide(ANP)and β⁃myosin heavy chain(β⁃MHC)mRNA in the heart of mice were also estimated
              by qPCR.[Leu31,Pro34]⁃NPY,a specific Y1 receptor agonist,was used to directly treat H9C2 cells in vitro. The mRNA levels of
              ANP and β ⁃ MHC in the cardiomyocytes were detected by qPCR,and the cell viability of H9C2 was measured by CCK ⁃ 8. The
              expressions of active β⁃catenin,phospho⁃glycogen synthesis kinase 3β(p⁃GSK3β)and total glycogen synthesis kinase 3β(t⁃GSK3β)in
              the heart and H9C2 cells were analyzed by Western blot. Nuclear β⁃ catenin accumulation was estimated by immunofluorescence
              staining. ICG001,a specific β⁃catenin inhibitor,was used to treat H9C2,and the cardiomyocyte hypertrophy and cell viability induced
              by[Leu31,Pro34]⁃ NPY were further examined. Results:Compared with the control group,cardiac NPY mRNA and protein
              expressions were increased significantly in ISO group(P < 0.05),in which it exhibited myocardial fiber arrangement disorder,high
              degree of myocardial fibrosis and increased expression of cardiac hypertrophy related gene. Compared with the ISO group,the
              myocardial damage and fibrosis were effectively alleviated in BIBO3304+ISO group,and the expression of cardiac hypertrophy related
              gene were decreased(P < 0.01). Compared with the control group,[Leu31,Pro34]⁃NPY increased ANP and β⁃MHC mRNA levels,

              and decreased cell viability in H9C2 cardiomyocytes(P < 0.01). Compared with the control group,the protein expressions of active β⁃
              catenin and p⁃GSK3β/t⁃GSK3β were increased in the heart of mice from ISO group(P < 0.05). Compared with the ISO group,the
              expressions of active β⁃catenin and p⁃GSK3β were decreased in BIBO3304+ISO group(P < 0.05). Compared with the control group,
             [Leu31,Pro34]⁃NPY increased expressions of active β⁃catenin and p⁃GSK3β,as well as facilitated nuclear β⁃catenin accumulation in
              the cardiomyocytes(P < 0.05). Compared with[Leu31,Pro34]⁃NPY group,BIBO3304 decreased β⁃catenin expression in the nucleus,
              and ICG001 effectively alleviated cardiomyocyte hypertrophy and cell viability reduction(P < 0.01). Conclusion:NPY/Y1 receptor
              mediates cardiomyocyte injury and fibrosis through β⁃catenin pathway.
             [Key words] NPY/Y1 receptor;β⁃catenin pathway;myocardial injury;cardiac fibrosis
                                                                            [J Nanjing Med Univ,2024,44(03):313⁃321]





                  近 年 来 ,心 源 性 猝 死(sudden cardiac death,        细胞表面不同亚型的受体可产生不同的生物学效
              SCD)的发病率显著增加并呈年轻化趋势,严重威胁                          应。Y1 受体是心肌细胞表面主要的表达亚型。高
              着人类的生命健康。SCD本质上表现为心脏电传导                           血压大鼠心肌组织Y1受体表达增加,参与调节心肌
                                                                               [7]
              功能紊乱,多发生于有心脏基础病变的心肌病患                             细胞的能量生成 。NPY 通过 Y1 受体可促进内皮
              者,如心肌肥厚、冠心病、心肌梗死等。这些疾病造                           细胞和血管平滑肌细胞的增殖和迁移。然而 NPY/
              成患者的心肌细胞发生不同程度的损伤,是猝死发                            Y1受体信号转导是否参与β肾上腺素受体持续激活
              生的物质基础       [1-2] 。了解心肌细胞损伤的诱因并探                 诱导心肌损伤目前尚未可知。经典 Wnt/β⁃catenin
              讨其相应的分子机制,对于心肌疾病的精准诊疗以                            信号通路在细胞生长、增殖、迁移以及凋亡等过程中
              及预防SCD猝死具有重要意义。                                   扮演重要角色。糖尿病性心肌病中,心肌组织糖原合
                  神经肽 Y(neuropeptide Y,NPY)是 1 种由 36 个          成酶激酶 3β(glycogen synthesis kinase 3β,GSK3β)
              氨基酸组成的小分子多肽,是心肌组织中含量最丰                            mRNA 下降,p⁃GSK3β增加,诱导细胞质中β⁃catenin
              富的神经肽类物质。心肌梗死、心衰等发生时,血                            入核,启动下游靶基因表达,导致细胞凋亡 。NPY
                                                                                                      [8]
                                                [3]
              清和心肌组织中NPY表达均显著增加 。然而NPY                          是否影响心肌细胞中经典Wnt信号通路未见相关报
              在心肌细胞中的功能目前没有统一的认识。研究                             道。基于此,本研究建立异丙肾上腺素(isoprena⁃
              发现NPY高表达对心血管系统具有损伤作用,可进                           line,ISO)诱导的小鼠心肌损伤模型和 Y1 受体特异
                                      [4]
              一步引发高血压和心肌肥厚 ;敲除NPY可有效缓解                          性激活剂[Leu31,Pro34]⁃NPY 诱导的 H9C2 细胞模
              缺血诱导的心肌细胞凋亡和功能障碍 。然而也有                            型,探讨 NPY/Y1 受体信号转导是否通过β⁃catenin
                                                [5]
              研究认为,缺乏NPY的急性心肌缺血小鼠表现出更                           信号通路诱导心肌细胞损伤。
                                                [6]
              严重的进行性心肌炎症和心肌纤维化 ,提示 NPY
                                                                1  材料和方法
              高表达可能是机体的一种反馈保护机制。因此深
              入探讨不同状态下 NPY 对心肌细胞的作用及相应                          1.1 材料
              机制具有重要意义。                                              C57BL/6J小鼠(6~8周龄)购自南京凯斯佳生物
                  目前已发现的NPY作用受体有8种亚型。激活                         科技有限公司,动物实验符合 3R 原则(伦理批文编
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