Skip to main content

Age-Dependent Effects on Functional Aspects in Human Satellite Cells

Buy Article:

$51.00 plus tax (Refund Policy)

Abstract:

Abstract: 

In humans aging is a complex process that determines many physical and metabolic alterations correlated to the accumulation of oxidative damage in different tissues. Sarcopenia is an age-related nonpathological condition that includes a progressive loss of mass and strength in skeletal muscle, associated with a decline in the fibers' functional capability. This condition could be correlated to abnormal reactive oxygen species (ROS) accumulation with consequent fiber oxidative damage. This complex situation is not only evident in mature muscle fibers but also in muscle resident satellite cells (involved in fiber damage repairing) in which some functional parameters, at least for that concerns the Ca2+ homeostasis, seem to be modified. In fact, our data show that there is an age-dependent increase of lipid peroxidation, in cultured myotubes (differentiated and fused satellite cells) after 7 days of in vitro differentiation. In these substrates also the capacity of these cells to produce Ca2+ transient in response to various stimuli (ATP, caffeine, nicotine, KCl) is, sometimes, drastically modified. In particular, the presence of an age-dependent defective status of excitation–contraction (EC) coupling apparatus is supported by a single cell Ca2+ analysis obtained from myotubes (derived from aged muscles) in the presence of 40 mM caffeine or 40 mM KCl. The alkaloid presence induces a complete emptying of ryanodine-dependent calcium stores indicating a probable integrity both of SR-terminal cisternae and/or the specific Ca2+ channel known as RyR1. However, if a sarcolemmal depolarization is induced by the addition of 40 mM KCl in the experimental medium then Ca2+ release RyR1-dependent can be observed only if Ca2+ is present in the experimental solution. These results suggest that the EC uncoupling status could be due to the alteration of the interaction between RyR and DHPR. The two receptors are present and functionally active in myotubes from aged donors but they are probably still not in the right localization. These results suggest that during donor's life the satellite cells undergo an aging process similar to the one observed in skeletal muscle tissue, even if they are in a quiescence status for most of the time.

Keywords: Ca2+transients; EC coupling; Sarcopenia; oxidative damage; satellite cells

Document Type: Research Article

DOI: http://dx.doi.org/10.1196/annals.1395.037

Affiliations: Dipartimento di Scienze Mediche di Base ed Applicate, CeSI–Centro Studi Invecchiamento, IIM-Istituto Interuniversitario di Miologia Università“G. d'Annunzio” Chieti–Pescara I-66013, Italy

Publication date: April 1, 2007

bsc/nyas/2007/00001100/00000001/art00038
dcterms_title,dcterms_description,pub_keyword
6
5
20
40
5

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more