Abstract
The existence of multipotent adipose-derived stem cells isolated from human orbital fat (OF) tissue has shown great therapeutic potential in tissue engineering and regenerative medicine. But the use of stem cells for therapeutic applications is influenced by their proliferative and differentiation potentials, which may be affected by the age of the donor. So far there is little knowledge about the effects of donor age on the biological properties of human orbital adipose-derived stem cells (OASCs). The intraorbital fat protrusion in the lower eyelids occurs as an aging process, and the protruded fat is routinely removed during aesthetic surgeries. Based on the ease of OF harvest and the availability of OASCs, we investigated in this study the relationship between age and the differentiation and proliferation potentials of human OASCs. Human orbital adipose samples were harvested from young (with normal lower eyelid appearance) and old donors (having protruded fat pads in the lower eyelids). The morphological properties of orbital adipocytes were assessed and the fat cell size displayed a decreasing trend with advancing age. OASCs were isolated from the fat samples, expanded in vitro and cultured under appropriate inducive conditions. Compared to the young cells, although no difference was found in the cell yield and phenotype expression, aged OASCs showed fewer progenitor cell numbers, reduced proliferative rates, increased senescent features and decreased differentiation potentials towards adipogenic, osteogenic and chondrogenic lineages. Our data suggested that using autologous OASCs from elderly patients for potential therapeutic purposes might be restricted.