Rinaldi Fabrizio, Zhang Yu, Mondragon-Gonzalez Ricardo, Harvey Jeffrey, Perlingeiro Rita C R
Lillehei Heart Institute, Department of Medicine, University of Minnesota, 4-128 CCRB, 2231 6th St. SE, Minneapolis, MN 55455 USA.
Department of Neurology, The First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
Skelet Muscle. 2016 Jun 14;6:21. doi: 10.1186/s13395-016-0092-8. eCollection 2016.
Duchenne muscular dystrophy (DMD) is an inherited lethal muscle wasting disease characterized by cycles of degeneration and regeneration, with no effective therapy. Growth differentiation factor 11 (GDF11), a member of the TGF-β superfamily and myostatin homologous, has been reported to have the capacity to reverse age-related skeletal muscle loss. These initial findings led us to investigate the ability of GDF11 to promote regeneration in the context of muscular dystrophy and determine whether it could be a candidate to slow down or reverse the disease progression in DMD.
Here, we delivered recombinant GDF11 (rGDF11) to dystrophin-deficient mice using the intra-peritoneal route for 30 days and evaluated histology and function in both steady-state and cardiotoxin-injured muscles. Our data confirmed that treatment with rGDF11 resulted in elevated levels of this factor in the circulation. However, this had no effect on muscle contractility nor on muscle histology. Moreover, no difference was found in the number of regenerating myofibers displaying centrally located nuclei. On the other hand, we did observe increased collagen content, which denotes fibrosis, in the muscles of rGDF11-treated dystrophic mice.
Taken together, our findings indicate no beneficial effect of treating dystrophic mice with rGDF11 and raise caution to a potential harmful effect, as shown by the pro-fibrotic outcome.
杜氏肌营养不良症(DMD)是一种遗传性致命性肌肉萎缩疾病,其特征为退化和再生循环,且尚无有效治疗方法。生长分化因子11(GDF11)是转化生长因子-β超家族成员,与肌肉生长抑制素同源,据报道具有逆转与年龄相关的骨骼肌损失的能力。这些初步发现促使我们研究GDF11在肌营养不良症背景下促进再生的能力,并确定它是否可能成为减缓或逆转DMD疾病进展的候选药物。
在此,我们通过腹腔内途径向缺乏肌营养不良蛋白的小鼠递送重组GDF11(rGDF11),持续30天,并评估稳态肌肉和心脏毒素损伤肌肉的组织学和功能。我们的数据证实,用rGDF11治疗导致循环中该因子水平升高。然而,这对肌肉收缩力和肌肉组织学均无影响。此外,在显示核位于中央的再生肌纤维数量上未发现差异。另一方面,我们确实观察到在接受rGDF11治疗的营养不良小鼠的肌肉中胶原含量增加,这表明存在纤维化。
综上所述,我们的研究结果表明,用rGDF11治疗营养不良小鼠没有有益效果,并提示可能存在潜在有害作用,如促纤维化结果所示。