Morphological and functional analyses of skeletal muscles from an immunodeficient animal model of limb-girdle muscular dystrophy type 2E

Muscle Nerve. 2018 Feb 24;58(1):133-144. doi: 10.1002/mus.26112. Online ahead of print.

Abstract

Introduction: Limb-girdle muscular dystrophy type 2E (LGMD2E) is caused by mutations in the β-sarcoglycan gene, which is expressed in skeletal, cardiac, and smooth muscles. β-Sarcoglycan-deficient (Sgcb-null) mice develop severe muscular dystrophy and cardiomyopathy with focal areas of necrosis.

Methods: In this study we performed morphological (histological and cellular characterization) and functional (isometric tetanic force and fatigue) analyses in dystrophic mice. Comparison studies were carried out in 1-month-old (clinical onset of the disease) and 7-month-old control mice (C57Bl/6J, Rag2/γc-null) and immunocompetent and immunodeficient dystrophic mice (Sgcb-null and Sgcb/Rag2/γc-null, respectively).

Results: We found that the lack of an immunological system resulted in an increase of calcification in striated muscles without impairing extensor digitorum longus muscle performance. Sgcb/Rag2/γc-null muscles showed a significant reduction of alkaline phosphate-positive mesoangioblasts.

Discussion: The immunological system counteracts skeletal muscle degeneration in the murine model of LGMD2E. Muscle Nerve, 2018.

Keywords: EDL; immunodeficient dystrophic mice; mesoangioblasts; smooth muscle; β-sarcoglycan.