LDL-壳聚糖-丝裂霉素C纳米靶向缓释制剂调控青光眼滤过术后瘢痕的实验研究

Excessive subconjunctival scarring is the main reason for the failure of glaucoma filtration surgery. The activation of human Tenon's capsule fibroblasts (HTFs) is believed to be responsible for wound healing and scar formation. Our preliminary study found that HTFs of normal people and glaucoma patients are both stimulated by TGF-β2 in a concentration-dependent and time-dependent manner and it shows a significant positive correlation between expression of LDL receptor and proliferation rate of HTFs, and then we proposed the hypothesis that "postoperative overexpression of LDLr in the activated HTFs may provide a novel target for more precise and rational design of drug delivery nanosystems". This project intends to stimulate three types of HTFs (normal people, glaucoma, and postoperative excessive subconjunctival scarring patients) by TGF-β2, and then detect the proliferation rate of HTFs and the expression of LDLr to verify the hypothesis. We will synthetize the LDL-chitosan-mitomycin C targeted nano-delivery and observe its effect in vivo. The purpose of this project is to propose a new design for scarring modulation in glaucoma filtration surgery.

青光眼滤过性手术失败的主要原因是滤过泡瘢痕化，而结膜囊成纤维细胞的异常增殖是瘢痕化的主要原因。本项目组前期研究验证了正常人和青光眼患者结膜囊成纤维细胞的增殖及其LDL受体的表达在TGF-β2刺激下均呈浓度依赖性和时间依赖性，同时发现LDL受体的表达和细胞的增殖成高度正相关，据此提出"青光眼滤过术后结膜囊成纤维细胞的LDL受体可被视为靶向性瘢痕调控的新型靶点"的假说。本项目拟将正常人、青光眼患者及滤过性手术后复发患者结膜囊成纤维细胞分别以TGF-β2刺激后，检测细胞增殖率和LDL受体的表达进行检测进一步验证该假说，并进一步以壳聚糖包封丝裂霉素C合成LDL-壳聚糖-丝裂霉素C靶向性纳米缓释制剂，进行活体动物实验观察LDL-壳聚糖-丝裂霉素C纳米缓释制剂的瘢痕调控效果。从而为探索新型靶向性给药系统的瘢痕调控提供实验依据，以期为应用于青光眼滤过区瘢痕调控治疗提供新的思路。

青光眼滤过性手术失败的主要原因是滤过泡瘢痕化，而结膜囊成纤维细胞的异常增殖是瘢痕化的主要原因。本项目组前期研究验证了正常人和青光眼患者结膜囊成纤维细胞的增殖及其LDL受体的表达在TGF-β2刺激下均呈浓度依赖性和时间依赖性，同时发现LDL受体的表达和细胞的增殖成高度正相关，据此提出“青光眼滤过术后结膜囊成纤维细胞的LDL受体可被视为靶向性瘢痕调控的新型靶点”的假说。本项目已将正常人、青光眼患者及滤过性手术后复发患者结膜囊成纤维细胞分别以TGF-β2刺激后，发现细胞增殖率呈时间依赖性和浓度依赖性，且LDL受体的表达与细胞增殖呈高度正相关。荧光共聚焦显微镜观察发现该三组结膜囊成纤维细胞与Dil-LDL的结合和内吞呈现时间依赖性。Westernblot检测发现此三组结膜囊组织中LDL受体表达依次为：复发组>青光眼组>正常人组。本研究已初步摸索出合成丝裂霉素C前体药物的部分实验条件，正逐步进行LDL-丝裂霉素C前体药物靶向性纳米缓释制剂的合成，并进行后续的体外细胞实验及活体动物实验观察LDL-丝裂霉素C前体药物靶向纳米缓释制剂的瘢痕调控效果。从而为探索新型靶向性给药系统的瘢痕调控提供实验依据，以期为应用于青光眼滤过区瘢痕调控治疗提供新的思路。