Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea.
Stem Cell Institute, ENCell Co., Ltd., Seoul 06072, Korea.
Int J Mol Sci. 2022 Aug 13;23(16):9059. doi: 10.3390/ijms23169059.
Myostatin is a member of the transforming growth factor-beta superfamily and is an endogenous negative regulator of muscle growth. This study aimed to determine whether an oral administration of expressing modified human myostatin (BLS-M22) could elicit sufficient levels of myostatin-specific antibody and improve the dystrophic features of an animal model of Duchenne muscular dystrophy (DMD; mouse). BLS-M22 is a recombinant engineered to harbor the pKV vector and poly-gamma-glutamic acid gene linked to a modified human myostatin gene. Serological analysis showed that anti-myostatin IgG titers were significantly increased, and serum creatine kinase was significantly reduced in the BLS-M22-treated mice compared to the control mice. In addition, treatment of BLS-M22 resulted in a significant increase in body weight and motor function (Rotarod behavior test). Histological analysis showed an improvement in the dystrophic features (fibrosis and muscle hypertrophy) of the mice with the administration of BLS-M22. The circulating antibodies generated after BLS-M22 oral administration successfully lowered serum myostatin concentration. Myostatin blockade resulted in serological, histological, and functional improvements in mice. Overall, the findings suggest the potential of BLS-M22 to treat DMD; however, further clinical trials are essential to ascertain its efficacy and safety in humans.
肌肉生长抑制素是转化生长因子-β超家族的成员,是肌肉生长的内源性负调节剂。本研究旨在确定口服表达修饰的人肌肉生长抑制素(BLS-M22)是否能引起足够水平的肌肉生长抑制素特异性抗体,并改善杜氏肌营养不良症(DMD;mdx 小鼠)动物模型的营养不良特征。BLS-M22 是一种重组蛋白,设计为携带 pKV 载体和多聚γ-谷氨酸基因,与修饰后的人肌肉生长抑制素基因相连。血清学分析显示,与对照组小鼠相比,BLS-M22 治疗的小鼠抗肌肉生长抑制素 IgG 滴度显著升高,血清肌酸激酶显著降低。此外,BLS-M22 的治疗导致体重和运动功能(旋转棒行为测试)显著增加。组织学分析显示,BLS-M22 给药后 mdx 小鼠的营养不良特征(纤维化和肌肉肥大)得到改善。BLS-M22 口服给药后产生的循环抗体成功降低了血清肌肉生长抑制素浓度。肌肉生长抑制素阻断导致 mdx 小鼠的血清学、组织学和功能改善。总体而言,这些发现表明 BLS-M22 有潜力治疗 DMD;然而,还需要进一步的临床试验来确定其在人类中的疗效和安全性。