Fiber type‐specific response of skeletal muscle satellite cells to high‐intensity resistance training in dialysis patients

Abstract

Increased myonuclear content of type II muscle fibers of dialysis patients who perform resistance training suggests that SC dysfunction is not the limiting factor for muscle growth.

Muscle satellite cell content and mRNA signaling in germ cell cancer patients – effects of chemotherapy and resistance training

“…From biopsy samples, serial sections (10 lm) were cut in a cryostat (À20 C) and stored at À80 C. Satellite cells were identified on sections stained with antibodies against Pax7, myosin Type I and laminin, as previously described [10]. The number of Pax7 cells associated with all fibers, and Type I and II fibers separately, was determined and expressed relative to the of number fibers included in the assessment.…”

High Intensity Training May Reverse the Fiber Type Specific Decline in Myogenic Stem Cells in Multiple Sclerosis Patients

“…The healthy controls and MS patients in the present study were slightly younger (i.e., mean age of 47.5 and 45.7, respectively) and our findings thus indicate that aging or inactivity per se may explain the lower SC content per fiber in type II fibers, while no significant effect of MS per se was observed. The effect of chronic disease on SC content in vivo in humans is only sparsely described (Snijders et al, 2011 ; Beenakker et al, 2012 ; Molsted et al, 2015 ) and none of these have included a healthy age-matched control group. Thus, while both type II diabetic patients (Snijders et al, 2011 ) and dialysis patients (Molsted et al, 2015 ) were reported to have a reduced SC content per fiber in type II compared to type I fibers, it is unclear if these fiber type differences were related to the disease per se and/or aging.…”

“…The effect of chronic disease on SC content in vivo in humans is only sparsely described (Snijders et al, 2011 ; Beenakker et al, 2012 ; Molsted et al, 2015 ) and none of these have included a healthy age-matched control group. Thus, while both type II diabetic patients (Snijders et al, 2011 ) and dialysis patients (Molsted et al, 2015 ) were reported to have a reduced SC content per fiber in type II compared to type I fibers, it is unclear if these fiber type differences were related to the disease per se and/or aging. Since both studies reported a mean patient age >50 years, the reported fiber type difference may in fact predominantly be related to aging (Verdijk et al, 2013 ) rather that to the specific pathological condition, as our data on MS vs. healthy controls indicate.…”

“…Very few studies have, to our knowledge, investigated the effect of resistance training on SC content in patients suffering from chronic diseases. In patients undergoing dialysis no changes were reported in type II fiber SC content following 16 weeks of resistance training (Molsted et al, 2015 ). However, in the latter study the authors did report an increase in the myonuclear content of type II fibers suggesting that SCs had proliferated and committed to the myogenic differentiation program at an earlier time-point (Molsted et al, 2015 ).…”

“…In contrast to aging, there is sparse knowledge concerning the SC content in humans suffering from chronic diseases. Studies in type II diabetes (Snijders et al, 2011 ), chronic obstructive pulmonary disorders (Theriault et al, 2014 ), rheumatoid arthritis (Beenakker et al, 2012 ) or patients undergoing dialysis (Molsted et al, 2015 ) does, however, not indicate a lower SC content in these conditions, although further research is necessary. So far, no studies have evaluated if a chronic neurological condition, such as MS, affects SC content and the ability of the SCs to proliferate and differentiate.…”