Tu Jiajie, Wan Chao, Zhang Fengjie, Cao Lianbao, Law Patrick Wai Nok, Tian Yuyao, Lu Gang, Rennert Owen M, Chan Wai-Yee, Cheung Hoi-Hung
School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China.
Institute of Clinical Pharmacology, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-Inflammatory and Immune Medicine, Anhui Medical University, Hefei, China.
Aging Cell. 2020 May;19(5):e13116. doi: 10.1111/acel.13116. Epub 2020 Apr 22.
WRN mutation causes a premature aging disease called Werner syndrome (WS). However, the mechanism by which WRN loss leads to progeroid features evident with impaired tissue repair and regeneration remains unclear. To determine this mechanism, we performed gene editing in reprogrammed induced pluripotent stem cells (iPSCs) derived from WS fibroblasts. Gene correction restored the expression of WRN. WRN mesenchymal stem cells (MSCs) exhibited improved pro-angiogenesis. An analysis of paracrine factors revealed that hepatocyte growth factor (HGF) was downregulated in WRN MSCs. HGF insufficiency resulted in poor angiogenesis and cutaneous wound healing. Furthermore, HGF was partially regulated by PI3K/AKT signaling, which was desensitized in WRN MSCs. Consistently, the inhibition of the PI3K/AKT pathway in WRN MSC resulted in reduced angiogenesis and poor wound healing. Our findings indicate that the impairment in the pro-angiogenic function of WS-MSCs is due to HGF insufficiency and PI3K/AKT dysregulation, suggesting trophic disruption between stromal and epithelial cells as a mechanism for WS pathogenesis.
WRN突变会引发一种名为沃纳综合征(WS)的早衰疾病。然而,WRN缺失导致组织修复和再生受损,从而出现早衰特征的机制仍不清楚。为了确定这一机制,我们对源自WS成纤维细胞的重编程诱导多能干细胞(iPSC)进行了基因编辑。基因校正恢复了WRN的表达。WRN间充质干细胞(MSC)表现出改善的促血管生成作用。对旁分泌因子的分析表明,肝细胞生长因子(HGF)在WRN MSC中表达下调。HGF不足导致血管生成不良和皮肤伤口愈合不佳。此外,HGF部分受PI3K/AKT信号通路调控,而该信号通路在WRN MSC中脱敏。同样,抑制WRN MSC中的PI3K/AKT通路会导致血管生成减少和伤口愈合不良。我们的研究结果表明,WS-MSC促血管生成功能的损害是由于HGF不足和PI3K/AKT失调,提示基质细胞和上皮细胞之间的营养破坏是WS发病机制之一。