Department of Biological Sciences, School of Life Sciences and Environment, Royal Holloway University of London, Surrey TW20 0EX, UK.
Developmental Biology and Cancer Research and Teaching Department, University College London Great Ormond Street Institute of Child Health, London WC1N 1EH, UK.
Int J Mol Sci. 2024 Jun 1;25(11):6113. doi: 10.3390/ijms25116113.
Periostin, a multifunctional 90 kDa protein, plays a pivotal role in the pathogenesis of fibrosis across various tissues, including skeletal muscle. It operates within the transforming growth factor beta 1 (Tgf-β1) signalling pathway and is upregulated in fibrotic tissue. Alternative splicing of Periostin's C-terminal region leads to six protein-coding isoforms. This study aimed to elucidate the contribution of the isoforms containing the amino acids encoded by exon 17 (e17+ Periostin) to skeletal muscle fibrosis and investigate the therapeutic potential of manipulating exon 17 splicing. We identified distinct structural differences between e17+ Periostin isoforms, affecting their interaction with key fibrotic proteins, including Tgf-β1 and integrin alpha V. In vitro mouse fibroblast experimentation confirmed the TGF-β1-induced upregulation of e17+ Periostin mRNA, mitigated by an antisense approach that induces the skipping of exon 17 of the gene. Subsequent in vivo studies in the D2. mouse model of Duchenne muscular dystrophy (DMD) demonstrated that our antisense treatment effectively reduced e17+ Periostin mRNA expression, which coincided with reduced full-length Periostin protein expression and collagen accumulation. The grip strength of the treated mice was rescued to the wild-type level. These results suggest a pivotal role of e17+ Periostin isoforms in the fibrotic pathology of skeletal muscle and highlight the potential of targeted exon skipping strategies as a promising therapeutic approach for mitigating fibrosis-associated complications.
纤调蛋白是一种多功能的 90kDa 蛋白，在包括骨骼肌在内的各种组织的纤维化发病机制中发挥关键作用。它作用于转化生长因子β 1（TGF-β1）信号通路，在纤维化组织中上调。纤调蛋白 C 末端区域的选择性剪接导致六个蛋白编码同工型。本研究旨在阐明含有外显子 17 编码氨基酸的同工型（e17+纤调蛋白）对骨骼肌纤维化的贡献，并研究操纵外显子 17 剪接的治疗潜力。我们鉴定了 e17+纤调蛋白同工型之间的明显结构差异，影响其与关键纤维化蛋白（包括 TGF-β1 和整合素α V）的相互作用。体外小鼠成纤维细胞实验证实，e17+纤调蛋白 mRNA 在外源 TGF-β1 诱导下上调，而反义方法诱导基因的外显子 17 跳跃则减轻了上调。随后在 Duchenne 肌营养不良症（DMD）的 D2. 小鼠模型中的体内研究表明，我们的反义治疗可有效降低 e17+纤调蛋白 mRNA 的表达，这与全长纤调蛋白蛋白表达的降低和胶原蛋白积累的减少相一致。经处理的小鼠的握力恢复到野生型水平。这些结果表明 e17+纤调蛋白同工型在骨骼肌纤维化病理中发挥关键作用，并强调了靶向外显子跳跃策略作为减轻纤维化相关并发症的有前途的治疗方法的潜力。
