Comparison of mRNA expression in Alde-High and Alde-Low EPCs. (A) The mRNA expression levels of each factor in HUVECs, Alde-High EPCs, and Alde-Low EPCs were examined by RT-PCR under normoxic (20% O2) or hypoxic (1% O2) conditions. Semiquantitative RT-PCR analysis was performed in 2 independent cycles. (B) The mRNA expression levels of the factors in HUVECs, Alde-High EPCs, and Alde-Low EPCs were measured by densitometry and expressed as histograms (striped bar indicates HUVECs; black bar, Alde-High EPCs; and white bar, Alde-Low EPCs). The expression levels seen in HUVECs under normoxic conditions were normalized to a value of 1 as the standard for each factor. *P < .05; **P < .01. (C-D) Western blot analyses were performed to examine HIF protein levels in HUVECs, Alde-High EPCs, and Alde-Low EPCs under hypoxic condition. Left panel represents the HIF-1α expression in ECs, and right panel represents the HIF-2α expression. Quantification of the protein levels was analyzed by a densitometer. The values shown are the averages of 3 independent experiments (mean ± SD). Data are expressed as fold induction compared to the values taken from HUVECs cultured under normoxic condition (20% O2). White bar indicates 20% O2; gray bar, 5% O2; black bar, 1% O2. *P < .05.
