Antioxidants Reduce Muscular Dystrophy in the dy2J/dy2J Mouse Model of Laminin α2 Chain-Deficient Muscular Dystrophy

Abstract

Congenital muscular dystrophy with laminin α2 chain-deficiency (LAMA2-CMD) is a severe neuromuscular disorder without a cure. Using transcriptome and proteome profiling as well as functional assays, we previously demonstrated significant metabolic impairment in skeletal muscle from LAMA2-CMD patients and mouse models. Reactive oxygen species (ROS) increase when oxygen homeostasis is not maintained and, here, we investigate whether oxidative stress indeed is involved in the pathogenesis of LAMA2-CMD. We also analyze the effects of two antioxidant molecules, N-acetyl-L-cysteine (NAC) and vitamin E, on disease progression in the dy 2J /dy 2J mouse model of LAMA2-CMD. We demonstrate increased ROS levels in LAMA2-CMD mouse and patient skeletal muscle. Furthermore, NAC treatment (150 mg/kg IP for 6 days/week for 3 weeks) led to muscle force loss prevention, reduced central nucleation and decreased the occurrence of apoptosis, inflammation, fibrosis and oxidative stress in LAMA2-CMD muscle. In addition, vitamin E (40 mg/kg oral gavage for 6 days/week for 2 weeks) improved morphological features and reduced inflammation and ROS levels in dy 2J /dy 2J skeletal muscle. We suggest that NAC and to some extent vitamin E might be potential future supportive treatments for LAMA2-CMD as they improve numerous pathological hallmarks of LAMA2-CMD.

Linking Oxidative Stress and DNA Damage to Changes in the Expression of Extracellular Matrix Components

“…In fact, dy 3K /dy 3K mice show high levels of oxidative stress in quadriceps at least from post-natal day 7 and increased Gclm and Sqstm1 expression, markers of oxidative stress, at post-natal day 21 ( Gawlik et al, 2019 ). Analysis of muscles from 3-week-old dy 2J /dy 2J mice and muscle biopsies from LAMA2-CMD patients (age ranging between 22 days and 29 years) also confirmed the presence of elevated levels of ROS in both cases ( Harandi et al, 2020 ). Moreover, the treatment of dy 2J /dy 2J mouse quadriceps and triceps muscles with the antioxidant N -acetylcysteine (NAC) partially rescued the motor function of dy 2J /dy 2J mice, reduced the number of apoptotic fibers, lowered the levels of inflammation markers and prevented fibrosis ( Harandi et al, 2020 ).…”

“…Analysis of muscles from 3-week-old dy 2J /dy 2J mice and muscle biopsies from LAMA2-CMD patients (age ranging between 22 days and 29 years) also confirmed the presence of elevated levels of ROS in both cases ( Harandi et al, 2020 ). Moreover, the treatment of dy 2J /dy 2J mouse quadriceps and triceps muscles with the antioxidant N -acetylcysteine (NAC) partially rescued the motor function of dy 2J /dy 2J mice, reduced the number of apoptotic fibers, lowered the levels of inflammation markers and prevented fibrosis ( Harandi et al, 2020 ). Vitamin E, another antioxidant, applied to the same mouse model reduced the number of apoptotic fibers and attenuated inflammation in quadriceps muscles, although, it did not improve motor function or reduce fibrosis ( Harandi et al, 2020 ).…”

“…Mutations in LAMA2 lead to a congenital muscular dystrophy (LAMA2-CMD; also known as merosin-deficient congenital muscular dystrophy type 1A, MDC1A) which is characterized by muscle weakness, fibrosis, and chronic inflammation ( Gawlik and Durbeej, 2011 ; Yurchenco et al, 2018 ). Recently, different mouse models of LAMA2-CMD (the dy 2J /dy 2J and dy 3K /dy 3K mouse models) and biopsies from LAMA2-CMD patients were used to address the impact of oxidative stress on this condition ( de Oliveira et al, 2014 ; Fontes-Oliveira et al, 2017 ; Gawlik et al, 2019 ; Kölbel et al, 2019 ; Harandi et al, 2020 ). These studies indicate that the muscles of Lama2 -deficient mice and LAMA2-CMD patients display an increase in oxidative stress both in early and more advanced stages of the disease, pointing to an important role of oxidative stress throughout disease progression ( Gawlik et al, 2019 ; Harandi et al, 2020 ).…”

“…Recently, different mouse models of LAMA2-CMD (the dy 2J /dy 2J and dy 3K /dy 3K mouse models) and biopsies from LAMA2-CMD patients were used to address the impact of oxidative stress on this condition ( de Oliveira et al, 2014 ; Fontes-Oliveira et al, 2017 ; Gawlik et al, 2019 ; Kölbel et al, 2019 ; Harandi et al, 2020 ). These studies indicate that the muscles of Lama2 -deficient mice and LAMA2-CMD patients display an increase in oxidative stress both in early and more advanced stages of the disease, pointing to an important role of oxidative stress throughout disease progression ( Gawlik et al, 2019 ; Harandi et al, 2020 ). In fact, dy 3K /dy 3K mice show high levels of oxidative stress in quadriceps at least from post-natal day 7 and increased Gclm and Sqstm1 expression, markers of oxidative stress, at post-natal day 21 ( Gawlik et al, 2019 ).…”

A Family of Laminin α2 Chain-Deficient Mouse Mutants: Advancing the Research on LAMA2-CMD

“…Additionally, compounds that modulate inflammation (glatiramer acetate, prednisolone) (Connolly et al, 2002;Dadush et al, 2010;Rabie et al, 2019) and anti-fibrotic compounds (halofuginone, losartan, and losartan derivative) have been shown to diminish muscle pathology in dy/dy, dy 2J /dy 2J , and dy W /dy W mice (Nevo et al, 2010;Elbaz et al, 2012;Meinen et al, 2012;Vohra et al, 2015). Lastly, compounds that modulate muscle growth (clenbuterol), calcium levels (caldecrin), metabolism (metformin), oxidative stress as well as exon skipping with phosphoroamidate morpholino oligomers have all shown a positive influence on the muscle phenotype in the different LAMA2-CMD mouse models (Hayes and Williams, 1998;Tomomura et al, 2011;Aoki et al, 2013;Fontes-Oliveira et al, 2018;Harandi et al, 2020; Table 6).…”