Figure 8.

Stage-Specific Effects of ApoA-I Infusions on the Antiapoptotic Effects of Mouse HDL Ex Vivo

Apoptosis was induced in HCAECs by serum withdrawal (0.5% v/v fetal bovine serum) for 22 h, then incubated with rHDL, apoA-I, mouse HDL (50 μg/ml), or PBS (vehicle) for 16 h. Treated cells were incubated with antibodies to detect annexin V (A) and caspase 3 (B) using flow cytometry. Treated cell lysates were subjected to Western blotting to detect pAkt and total Akt (expressed as pAkt/Akt) (C) and Bcl-xL (D). Ly294002 (2 μmol/l) was added to inhibit PI3K/Akt signaling (E). Even protein loading was confirmed using α-tubulin. Data are mean ± SEM; n = 6 mice HDL/treatment group performed in duplicate. *p ≤ 0.05 compared with serum-starved controls, ^#p ≤ 0.05 compared with cells treated with mouse HDL from PBS-infused mice, ^γp ≤ 0.05 compared with cells treated with mouse HDL from apoA-I–infused early-stage mice. Bcl-xL = B-cell lymphoma-extra large; other abbreviations as in Figures 1 and 7.