RESUMO
BACKGROUND: Adipose tissue-derived stromal cells (ADSCs) are being recognized as a source of stem cells potentially useful for cardiovascular repair. We analysed the abundance and angiogenic activity of adipose tissue-derived progenitor cells (PCs) in elderly patients most likely to benefit from this novel source of stem cells. MATERIALS AND METHODS: Fifty-two subjects (aged 68 ± 13 years) with variable degrees of cardiovascular risk underwent abdominal surgery for intercurrent diseases. Visceral adipose tissue (3 ± 1 g visceral fat per patient) was processed with type-1 collagenase to obtain ADSCs from the stromal-vascular fraction. Adipose tissue-derived PCs were quantified by flow cytometry as %CD45(-)/CD34(+)/CD133(+) cells of total ADSCs. Matrigel angiogenesis assay was used to analyse the ability of ADSCs to form tubes or networks. RESULTS: We found no correlations between number of CD45(-)/CD34(+)/CD133(+) or total ADSCs and quantitative risk parameters including total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, waist circumference, body mass index, and systolic and diastolic arterial pressure. However, increasing age (r = -0·31, P < 0·05) significantly and inversely correlated with levels of adipose tissue-derived CD45(-)/CD34(+)/CD133(+) cells in Matrigel angiogenesis assays; increasing age (r = -0·29, P < 0·05) was related to a reduction of ADSC-derived tubulization. CONCLUSIONS: Ageing may alter the availability of adipose tissue-derived CD45(-)/CD34(+)/CD133(+) cells and their angiogenic functional capacity. Such changes may impair the use of adipose tissue as source of autologous PCs in elderly patients.
