Background: Whether aging modifies mesenchymal stem cell (MSC) properties is unknown.

Aim: To compare the differentiation capacity of human CD105(+) MSCs obtained from young and elderly donors.

Methods and results: Cells were obtained from young (n=10, 24±6.4 years) and elderly (n=9, 77±8.4 years) donors. Cell senescence was assessed by telomere length assays and lipofuscin accumulation. Cell pluripotentiality was analysed by adipogenic and osteogenic induction media, and myocyte phenotype was attempted with 5-azacytidine (5-AZ). Immunofluorescence, Western blot, transmission electron microscopy and fluo-4 confocal imaging were used to analyse the sarcomere, gap junctions and Ca(2+) dynamics. Cells obtained from young and elderly donors showed no significant differences in relative telomere length (40.1±6.4% and 40.3±3.6%, p=0.9) and lipofuscin accumulation. Adipogenic and osteogenic potential of CD105(+) MSCs was demonstrated. 5-AZ induced increased expression of sarcomeric proteins without complete sarcomere organization. Treated cells also showed increased presence of connexin-43 both in young and old donor-derived cells. Intercellular communications were verified by the observation of gap junctions and passage of Ca(2+) between neighbouring cells. Spontaneous Ca(2+) raises did not significantly increase after 5-AZ treatment in both age groups.

Conclusion: Age does not influence the adipogenic and myogenic differentiation potential of human CD105(+) MSCs.