Lack of PKC? Promotes Regenerative Ability of Muscle Stem Cells in Chronic Muscle Injury.

ABSTRACT: Duchenne muscular dystrophy (DMD) is a genetic disease characterized by muscle wasting and chronic inflammation, leading to impaired satellite cells (SCs) function and exhaustion of their regenerative capacity. We previously showed that lack of PKC? in mdx mice, a mouse model of DMD, reduces muscle wasting and inflammation, and improves muscle regeneration and performance at early stages of the disease. In this study, we show that muscle regeneration is boosted, and fibrosis reduced in mdx?-/- mice, even at advanced stages of the disease. This phenotype was associated with a higher number of Pax7 positive cells in mdx?-/- muscle compared with mdx muscle, during the progression of the disease. Moreover, the expression level of Pax7 and Notch1, the pivotal regulators of SCs self-renewal, were upregulated in SCs isolated from mdx?-/- muscle compared with mdx derived SCs. Likewise, the expression of the Notch ligands Delta1 and Jagged1 was higher in mdx?-/- muscle compared with mdx. The expression level of Delta1 and Jagged1 was also higher in PKC?-/- muscle compared with WT muscle following acute injury. In addition, lack of PKC? prolonged the survival and sustained the differentiation of transplanted myogenic progenitors. Overall, our results suggest that lack of PKC? promotes muscle repair in dystrophic mice, supporting stem cells survival and maintenance through increased Delta-Notch signaling.

SUBMITTER: Fiore PF 

PROVIDER: S-EPMC7037041 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature