Tan Jian, Xu Yipin, Han Fang, Ye Xinhai
Department of Plastic Surgery, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China.
Department of Facial Plastic and Reconstructive Surgery, Eye and ENT Hospital of Fudan University, Shanghai 200031, China.
Aging (Albany NY). 2019 Feb 6;11(3):908-920. doi: 10.18632/aging.101790.
Adipose-derived stem cells (ASCs) have a demonstrative therapeutic potential in aging-associated facial nerve regeneration, in which ASCs work as a source of Schwann cells therapy as an alternative to autologous nerve grafts. However, the transplantation of ASCs may induce local fibrosis, which causes inferior outcome. Here, we aimed to use genetic modification approaches to reduce the fibrogenic properties of ASCs to improve their therapeutic effects on facial nerve regeneration. Since procollagen-lysine 1, 2-oxoglutarate 5-dioxygenase 1 (PLOD1) is essential for hydroxylation of lysine residues in collagen telopeptides and for collagen pyridinoline cross-link formation during fibrosis, and since we found that ASCs expressed high levels of PLOD1, we depleted PLOD1 in ASCs by expression of either a short-hair interfering RNA for PLOD1 (shPLOD1) or a microRNA-449 (miR-449), the latter of which targets PLOD1 mRNA to suppress protein translation. Transplantation of either ASCs-shPLOD1 or ASCs-miR-449 or ASCs-control to repair a 6mm-gap in rat facial nerve was compared. Either ASCs-shPLOD1 or ASCs-miR-449 exhibited a better facial nerve function. Mechanistically, ASCs-shPLOD1 or ASCs-miR-449 significantly and similarly reduced the fibrosis in the injured region, likely through suppression of reactive oxygen species (ROS) and activation of myofibroblasts.
脂肪来源干细胞（ASCs）在衰老相关的面神经再生中具有显著的治疗潜力，其中ASCs作为雪旺细胞治疗的来源，可替代自体神经移植。然而，ASCs的移植可能会诱导局部纤维化，导致治疗效果不佳。在此，我们旨在采用基因改造方法降低ASCs的纤维化特性，以提高其对面神经再生的治疗效果。由于原胶原赖氨酸1,2-酮戊二酸5-双加氧酶1（PLOD1）对于胶原末端肽中赖氨酸残基的羟基化以及纤维化过程中胶原吡啶啉交联的形成至关重要，并且我们发现ASCs表达高水平的PLOD1，因此我们通过表达针对PLOD1的短发夹干扰RNA（shPLOD1）或微小RNA-449（miR-449）来消耗ASCs中的PLOD1，后者靶向PLOD1 mRNA以抑制蛋白质翻译。比较了ASCs-shPLOD1、ASCs-miR-449或对照ASCs移植修复大鼠面神经6mm间隙的情况。ASCs-shPLOD1或ASCs-miR-449均表现出更好的面神经功能。从机制上讲，ASCs-shPLOD1或ASCs-miR-449显著且相似地减少了损伤区域的纤维化，可能是通过抑制活性氧（ROS）和激活肌成纤维细胞来实现的。
