Perilipin 5在骨骼肌损伤后再生和修复中的作用机制研究

The proliferation and differentiation can regulate and repaire skeletal muscle injury. It is very important for the study on proliferation, differentiation of myoblast and the satellitecell of mature organisms. According to our result data, we found that the expression of Plin5 was higher in muscle tissue, and the expression abundance has changed during the process of proliferation, differentiation and atrophy. Thus we hypothesized that Plin5 would play a role on muscle development. In order to validate the biological function comprehend the regulation mechanisms of Plin5, firstly, we will detected the time-sequential expression of Plin5 during myoblast differentiation, and then evaluated the effect of Plin5 on myoblast proliferation, differentiation, myotube formation and some related signaling pathway factors from morphology to gene expression levels by constructing the expression and interference vector of Plin5 to treat C2C12 myoblast and constructed Plin5 knockout mice muscle injury model and myoatrophy model. Next, in order to further consummate cell trial in vitro and establish a base for function study of Plin5, we also detected the effect of Plin5 on the regeneration and repair after muscular injury and by injecting the Plin5 adenovirusin into the constructed muscle injury model model.

骨骼肌损伤相关肌病的发生及恢复均离不开卫星细胞的增殖与分化，研究成肌细胞及成熟生物体内卫星细胞的成肌过程有重要的研究意义。我们的初步研究发现Plin5在肌肉组织中高表达，并且在禁食和高脂饮食的情况下，骨骼肌内的Plin5明显升高，因此我们推测Plin5可能在肌肉发育中发挥一定的作用。为验证 Plin5的细胞学功能，拟通过检测Plin5在成肌细胞分化过程中的时序表达；构建Plin5表达载体和干扰载体侵染 C2C12 成肌细胞，以及Plin5敲除小鼠的肌损伤模型，采用细胞分子生物学等技术，从形态学和基因表达水平检测Plin5对成肌细胞增殖、分化、肌管形成及其相关信号通路因子的影响，为初步确定Plin5参与肌肉发育调控的作用机理提供参考依据。同时我们通过肌肉局部注射 Plin5 腺病毒，检测其对肌损伤后再生修复的作用，为深入研究其在肌肉发育中的作用奠定基础。

骨骼肌损伤相关肌病的发生及恢复均离不开卫星细胞的增殖与分化，研究成肌细胞及成熟生物体内卫星细胞的成肌过程有重要的研究意义。脂滴蛋白Plin5在骨骼肌和肝脏等组织中高表达，其与疾病发生之间的关系目前尚不清楚。本研究在已有的工作基础上，通过研究Plin5在C2C12 成肌细胞的增殖分化中的影响及并观察 Plin5 敲除后对C2C12细胞增殖能力的影响，在细胞水平揭示Plin5在成肌发育过程中的可能作用；并利用 plin5 敲除小鼠模型，检测了肌肉损伤修复过程中Plin5的差异表达以及对信号通路分子的影响，测定了铁死亡信号通路。结果发现Plin5缺失降低了骨骼肌细胞脂质积累，促进脂肪酸氧化，激活PPARα，促进线粒体增殖，从而促进脂解。这个过程引起大量的ROS产生，进一步加重骨骼肌铁死亡。本研究结果不仅有助于认识Plin5参与肌肉发育调控的作用机理，以及在骨骼肌损伤修复中的作用和机制，还为肌病的治疗提供新的依据。