Effects of 1,25D3 treatment on quiescence- and senescence-associated genes.

A Expression of quiescence markers and densitometric quantification of semiquantitative RT-PCR results of hMSC (P3) treated with or without 1,25D3. Cells from five different donors were used. For each donor the Fold Change was calculated by comparing the expression of 1,25D3 treated cells with control cells. The results are shown as mean+SEM. The gene expression levels of FOXO1a, FOXO3a, FOXO4, NANOG, TxNIP, TP53 were induced by 1,25D3 treatment over 3 passages. (FOXO1a: forkhead box 1a, FOXO3a: forkhead box 3a, FOXO4: forkhead box 4, NANOG: Nanog homeobox, TxNIP: thioredoxin interacting protein, TP53: tumor protein p53). B Expression of senescence markers and densitometric quantification of semiquantitative RT-PCR results of hMSC treated with or without 1,25D3 over at least four passages. 1,25D3 treatment reduced P16 expression (p<0.05) and induced P15 expression in cells at P4 compared to control cells. P27 and P21 gene expression in P4 showed no (P27) or only very weak (P21) induction by 1,25D3 treatment. Densitometric quantification of the semi-quantitative PCR results revealed downregulation of PSG1 and almost no change in the expression of PSG5 at P4 in 1,25D3 stimulated hMSC. The Relative Fold change represents the factor of different gene expression levels in 1,25D3 treated hMSC versus control cells. Expression profile of senescence-associated genes was determined in P4. Cells from three different donors were used. For each donor the Fold Change was calculated by comparing the expression of 1,25D3 treated cells with control cells. The results are shown as mean+SEM. (*, p<0.05, student's t-test).