shRNA靶向沉默IGFBP-3联合BM-MSCs移植治疗老龄大鼠勃起功能障碍的研究

We have confirmed the higher expression of insulin-like growth factor binding protein-3 (IGFBP-3) in corpus carvernosum in old rats. We also have confirmed short hairpin RNA (shRNA) constructs targeting IGF-BP3 ameliorate aging-related ED in the rat in the short period. However, the long-term effects are limited. An effective and stable expression target gene and vector is the key for gene therapy of ED. The bone marrow derived mesenchymal stem cells (BM-MSCs) have been confirmed is an ideal vector for cell-based gene therapy.Furthermore, IGF-1 modified BM-MSCs have also been confirmed ia an long-term effective tactile for treatment of diametic rats. Based on our previous series studies, in this study, we first modified the BM-MSCs with short hairpin RNA (shRNA) constructs targeting IGF-BP3, and then investigated the feasibility of intracavernous transplantation of the modified BM-MSCs for improving erectile function in streptozocin (STZ)-induced diabetic rats, and studied the possible mechanism of intracavernous transplantation. It may find a new target for gene therapy of ED and give a basement for the clinical trial.

我们在前期研究中已经证实胰岛素样生长因子结合蛋白-3（IGFBP-3)在老龄大鼠阴茎海绵体组织中明显增加，同时采用RNA干扰技术抑制IGFBP-3的表达能够短期明显改善老龄大鼠的勃起功能，但长期治疗效果欠佳，能否找到在体内长期稳定表达并具有很好长期治疗效果的靶基因和载体？骨髓间充质干细胞(BM-MSCs)课题组已经证实，适宜作为基因治疗的良好载体；同时课题组已经发现采用IGF-1基因修饰BM-MSCs治疗糖尿病ED能够长期明显改善勃起功能。因此，本研究拟在前期大量研究基础之上对采用短发夹RNA (shRNA) 靶向沉默IGFBP-3基因，同时转染 BM-MSCs，探讨靶向沉默IGFBP-3基因联合BM-MSCs移植长期改善老龄大鼠勃起功能的可行性，以期为老年性ED的治疗提供一全新策略；同时探索其可能的分子机制，为确立ED治疗的新靶标提供科学依据，同时为进一步临床开发基因治疗药物奠定基础。

本研究在前期研究基础之上进行研究，我们在前期研究中已经证实胰岛素样生长因子结合蛋白-3（IGFBP-3)在老龄大鼠阴茎海绵体组织中明显增加；同时采用RNA干扰技术抑制IGFBP-3的表达能够短期明显改善老龄大鼠的勃起功能；；采用IGF-1基因修饰BM-MSCs治疗糖尿病ED能够长期明显改善勃起功能。本研究寻找在体内长期稳定表达并具有长期治疗效果的靶基因和载体，采用骨髓间充质干细胞(BM-MSCs)为细胞载体，鉴定分离BM-MSCs，采用病毒载体构建IGFBP-3 shRNA，采用短发夹RNA (shRNA) 靶向沉默IGFBP-3基因，同时转染 BM-MSCs，探讨靶向沉默IGFBP-3基因联合BM-MSCs移植长期改善老龄大鼠勃起功能的可行性，发现靶向沉默IGFBP-3基因联合BM-MSCs移植在1、2、3月能够改善大鼠的阴茎海绵体内压（ICP），能够提高阴茎海绵体平滑肌容量，能够提高NOS和cGMP的含量，为老年性ED的治疗提供了一全新策略；同时探索了其可能的分子机制，为确立ED治疗的新靶标提供科学依据，同时为进一步临床开发shRNA靶向抑制IGFBP-3联合干细胞治疗奠定了基础。