Miniature Pigs Carrying <i>DMD</i> Exon51 Deletion Suffered from Severe Myocardial Damage, Accelerated Muscle Atrophy and Malabsorption

Abstract

Duchenne muscular dystrophy (DMD), inherited in an X-linked recessive manner, is a lethal disease affecting about 1/3600 males at birth. Mutations in the DMD gene have been shown to be the key determinant of the occurrence of DMD disease. Nowadays, removal of DMD exon 51 has been used as a common therapeutic intervention in disease animal models. Despite all these efforts, the clinical significance of DMD exon 51 has hardly been explored in large animals. Our study aimed to investigate the role of DMD exon 51 in the pathogenesis of DMD disease. We generated cell clones and miniature pigs lacking DMD exon 51 by CRISPR-Cas9 system. Significant changes in cell membrane integrity and apoptosis were found in genetically modified cell clones. All DMD pigs showed the accelerated pathological process of Duchenne muscular dystrophy. In addition, the ability of the small intestine of DMD pigs to digest and absorb nutrients was significantly reduced, compared to wild-type littermates. To conclude, this research could assist in our understanding of the pathological process of Duchenne muscular dystrophy. The findings of our investigation complemented those of earlier studies and might provide new insights into slow down the progression of this disease. Funding: This work was supported by grants from National Natural Science Foundation of China (No. 31572345 and 31472053), the Program for JLU Science and Technology Innovative Research Team (2017TD-28), the Fundamental Research Funds for the Central Universities, the Humanized IAPP gene preparation of human diabetes miniature swine model. Jilin Province Science and Technology Development Plan Project (No.20170623035TC) and the Program for Changjiang Scholars and Innovative Research Team in University in China (No. IRT16R32). Declaration of Interest: The authors declare no competing interest. Ethical Approval: All animal studies were approved by the Animal Welfare and Research Ethics Committee at Jilin University, and all procedures were conducted strictly in accordance with the Guide for the Care and Use of Laboratory Animals. All surgeries were performed under anesthesia, and every effort was made to minimize animal suffering.