Cellular lipids changes during Adipose-derived Stem Cells osteogenic differentiation

PARRA, L; CASALI, CI; SETTON-AVRUJ, CP; FERNÁNDEZ-TOME, MC

Paraná

Congreso; LIV Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2018

SAIB

Adipose-derived Stem Cells (ASC) constitute a promising tool for many applications in regenerative medicine. In the last years, a large number of works describing the mechanism underlying ASC differentiation was published but the role of lipid metabolism in this process is still unclear. The aim of this work was to evaluate whether osteogenic differentiation of ASC involves changes on lipids content and biosynthesis. For this, adipose tissue was removed from adult Wistar rats and ASC were isolated and culture in low glucose DMEM through 3 passages. After that, ASC were characterized by measuring their capacity to differentiate into the osteogenic and adipogenic lineages and the expression of CD90. Third passage ASC was cultured and in vitro differentiated or not to an osteoblast phenotype with low glucose DMEM containing 100 nM dexamethasone, 10 mM β-glycerophosphate and 5 µg/ml ascorbic acid 2-phosphate. After 21 days, cellular lipids and phospholipid (PL) species were quantified. To evaluate lipid synthesis, cells were incubated in the presence of 0,1 µCi [14C(U)]-glycerol for 3h, and then lipids biosynthesis were determined. After treatment, differentiated cells showed a decrease on lipid synthesis and phospholipid content compared to control cells. Total PL content decreased by 54%, while PL species content varied in a different manner, leading to a different PL profile with an enrichment in sphingomyelin in differentiated cells membranes. PL, Diacylglycerol (DAG) and Triacylglycerol (TAG) synthesis decreased by 90, 87 and 86%, respectively. Results show that ASC osteogenic differentiation is accompany by changes on lipid synthesis and content.