Satellite cells and training in the elderly

Abstract

In the present review, we describe the effects of ageing on human muscle fibres, underlining that each human muscle is unique, meaning that the phenotype becomes specifically changed upon ageing in different muscles, and that the satellite cells are key cells in the regeneration and growth of muscle fibres. Satellite cells are closely associated with muscle fibres, located outside the muscle fibre sarcolemma but beneath the basement lamina. They are quiescent cells, which become activated by stimulation, like muscle fibre injury or increased muscle tension, start replicating and are responsible for the repair of injured muscle fibres and the growth of muscle fibres. The degree of replication is governed by the telomeric clock, which is affected upon excessive bouts of degeneration and regeneration as in muscular dystrophies. The telomeric clock, as in dystrophies, does not seem to be a limiting factor in ageing of human muscle. The number of satellite cells, although reduced in number in aged human muscles, has enough number of cell divisions left to ensure repair throughout the human life span. We propose that an active life, with sufficient general muscular activity, should be recommended to reduce the impairment of skeletal muscle function upon ageing.

Effects of resistance training on fast- and slow-twitch muscles in rats

“…This increase in satellite cell number was also found in top-level powerlifters by [43]. The increase in the number of satellite cells could be due to asymmetric division of satellite cells and will make the muscle more responsive to further adaptation [24,46].…”

Current Controversies in Stem-Cell Treatment of Urinary Incontinence in Women

“…Two studies [3,4] also used autologous fibroblasts for the urethra submucosa, and the study by Lee [5] used stem cells from heterologous umbilical cord. These authors based their approach on a paper by Thornell et al [6], which confirmed that autologous muscle cell efficiency decreases with age.…”

“…The stem-cell culture methods also varied considerably according to the author, although even more importantly, there was considerable variation in the number of stem cells to be injected (range, 1x10 6 to 4.3x10 6 ± 1.9x10 8 ). Some papers stressed research on the ideal number of stem cells; for instance, the randomized studies [1] and [2] compared 2 doses: [1] had 3 arms and found no correlation between the outcomes and the doses used, whereas the other [2] achieved better efficacy in patients who received doses > 32x10 6 .…”

Adult stem cells derived from skeletal muscle — biology and potential

“…Besides paired box transcription factors, satellite cells also express M-cadherin, c-Met, Foxk1, syndecans 3, 4, and CD106, while the expression of CD34 can not be considered as strict marker of human satellite cells [27][28][29]. However, a more reliable marker of satellite cells in human muscle is CD56 (neural cell adhesion molecule) [30]. The assessment of differentiation potential showed that skeletal muscle satellite cells are strictly monopotential -they are committed to myogenesis [31,32].…”