Impaired muscle stem cell function and abnormal myogenesis in acquired myopathies

Abstract

Skeletal muscle possesses a high plasticity and a remarkable regenerative capacity that relies mainly on muscle stem cells. Molecular and cellular components of the muscle stem cell niche, such as immune cells, play key roles to coordinate muscle stem cell function and to orchestrate muscle regeneration. An abnormal infiltration of immune cells and/or imbalance of pro- and anti-inflammatory cytokines could lead to muscle stem cell dysfunctions that could have long lasting effects on muscle function. Different genetic variants were shown to cause muscular dystrophies that intrinsically compromise muscle stem cell function and disturb their microenvironment leading to impaired muscle regeneration that contributes to disease progression. Alternatively, many acquired myopathies caused by comorbidities (e.g., cardiopulmonary or kidney diseases), chronic inflammation/infection, or side effects of different drugs can also perturb muscle stem cell function and their microenvironment. The goal of this review is to comprehensively summarize the current knowledge on acquired myopathies and their impact on MuSC function. We further describe potential therapeutic strategies to restore muscle stem cell regenerative capacity.

Effects of Copy Number Variations in the Plectin (PLEC) Gene on the Growth Traits and Meat Quality of Leizhou Black Goats

“…Therefore, we believe that CNVs in the PLEC gene play an important role in regulating the growth traits and meat quality of LZBGs. This effect is primarily attributed to the multiple regulatory effects of PLEC on muscle development, as other researchers have demonstrated in previous studies [5,[44][45][46][47].…”

“…On the other hand, PLEC prevents ubiquitination by stabilizing Dvl-2, thereby reducing the level of LC3-labeled Dvl-2 and antagonizing the autophagy system. The inhibition of autophagy results in incomplete skeletal muscle recovery and disrupts muscle regeneration [46,47]. In this study, the traits of body weight, chest circumference, carcass weight, and the cross-sectional area of the longissimus dorsi muscle were directly influenced by muscle mass, leading to significant differences in the means for these traits between the different CNV types.…”

The frequency of sarcopenia has increased in patients with glomerulonephritis

“…Two studies showed that the proteasomedependent degradation of MyoD increased in muscle cells, and muscle loss developed with glucocorticoid treatment. 24,25 It was reported in another study that ubiquitin-proteasome-dependent myogenin levels decreased, and muscle atrophy occurred in dexamethasone-induced muscle cells. 26 Recent studies emphasize that calcineurin and mTOR inhibitors, which are other immunosuppressive agents used in patients, also cause muscle atrophy since it disrupts protein metabolism.…”

“…It has been shown in different studies that glucocorticoids can cause skeletal muscle loss by increasing or suppressing transcription factors such as MyoD and myogenin, which have an anabolic role in skeletal muscle differentiation, and Forkhead Box O (FOXO), which has a catabolic role. Two studies showed that the proteasome‐dependent degradation of MyoD increased in muscle cells, and muscle loss developed with glucocorticoid treatment 24,25 . It was reported in another study that ubiquitin‐proteasome‐dependent myogenin levels decreased, and muscle atrophy occurred in dexamethasone‐induced muscle cells 26 .…”

Transcriptomic gene signatures measure satellite cell activity in muscular dystrophies

“… 15 , 16 Diseases in which satellite cells are compromised by environmental factors can be added to this classification. 17 …”