Abstract
The muscle membrane, sarcolemma, must be firmly attached to the basal lamina. The failure of proper attachment results in muscle injury, which is the underlying cause of Duchenne muscular dystrophy (DMD), where mutations in the dystrophin gene disrupts the firm adhesion. In DMD patients, even moderate contraction causes damage, leading to progressive muscle degeneration. The damaged muscles are repaired through myogenesis. Consequently, myogenesis is highly active in DMD patients, and the repeated activation of myogenesis leads to the exhaustion of the myogenic stem cells. Therefore, approaches to reducing the risk of the exhaustion are to develop a treatment that strengthens the interaction between the sarcolemma and the basal lamina, and increases the efficiency of myogenesis. Galectin-3 is an oligosaccharide-binding protein and known to be involved in cell-cell interactions and cell-matrix interactions. Galectin-3 is expressed in myoblasts and skeletal muscle while its function in muscle remains elusive. In this study, we found evidence that galectin-3 and the monosaccharide N-acetylglucosamine, which increases the ligands (oligosaccharides) of galectin-3, promotes myogenesis in vitro. Moreover, in the mdx mouse model of DMD, treatment with N-acetylglucosamine increased the muscle force production. Our results demonstrate that treatment with N-acetylglucosamine can mitigate the burden of DMD.
Footnotes
A glycobiology therapy for Duchenne muscular dystrophy
Abbreviations CRD: Carbohydrate recognition domain
DGC: dystrophin-associated glycoprotein complex
DMD: Duchenne muscular dystrophy
DM: Differentiation medium
DMEM: Dulbecco’s modified Eagle’s medium
DAPI: 4’,6-diamidino-2-phenylindole
EDL: extensor digitorum longus
FOV: Field of view
G3KO: Galectin-3 null
Gal: Galactose
GlcNAc: N-Acetylglucosamine
GM: Growth medium
LacNAc: N-Acetyllactosamine
MD: Muscular dystrophy
MGAT5: α1,6-mannosyl glycoprotein 6-βGlcNAc transferase
MHC: Myosin heavy chain
PBS: Phosphate buffered saline
PS: Phosphatidylserine
UDP: Uridine diphosphate