Mesenchymal Stem Cells Derived from Rat Epicardial Versus Epididymal Adipose Tissue

Objective(s) Some investigation has indicated that adipose-derived stem cells possess different surface epitopes and differentiation potential according to the localization of fat pad from which the cells were derived. In the present study proliferation capacity and aging of such cells were explored. Materials and Methods Adherent cells were isolated from the collagenase digests of adipose tissues excised from rat epicardial and epididymal regions and propagated with several subcultures. The cells were then investigated whether or not they were able to differentiate into bone, cartilage and adipose cell lineages. Studied cells from two adipose tissues were also compared with respect to their in vitro proliferation capacity. The presence of senescent cells in the culture was determined and compared using senescence-associated (SA) ß-galactosidase staining method. Results Successful differentiations of the cells were indicative of their mesenchymal stem cells (MSCs) identity. Epicardial adipose-derived cells tended to have a short population doubling time (45±9.6 hr) than the epididymal adipose-derived stem cells (69±16 hr, P< 0.05). Colonogenic activity and the growth curve characteristics were all better in the culture of stem cells derived from epicardial compared to epididymal adipose tissue. Comparatively more percentage of senescent cells was present at the cultures derived from epididymal adipose tissue (P< 0.05). Conclusion Our data emphasize on the differences existed between the stem cells derived from adipose depots of different anatomical sites in terms of their proliferative capacity and in vitro aging. Such data can help understand varying results reported by different laboratories involved in adipose stem cell investigations.