Figure 2.  .

PA and insulin cooperatively rescue retinal neurons from IL-1β−induced apoptosis. (A) R28 cells were treated with vehicle, insulin (10 nM), PA (50 μM), or insulin and PA in the presence or absence of IL-1β (10 ng/mL) and/or rapamycin (100 nM) for 24 hours. The number of pyknotic nuclei was determined by DAPI staining, then counted and expressed as a percentage of the total number of cells. (P < 0.0001 ANOVA F = 54.53, *P < 0.05; n = 3 independent experiments per condition, ⧫ significantly different from PA + IL-1β and Ins + IL-1β). (B) R28 cells were serum-starved for 4 hours before stimulation with PAs of different fatty acid compositions for 15 minutes. Western blots then were performed to assess p70 S6K Thr³⁸⁹ phosphorylation and p70 S6K (∼70 kilodaltons [kDa] molecular weight) levels. A representative blot from n = 3 independent biologic experiments is shown. (C) R28 cells were stimulated with either insulin (10 nM), PA (50 μM), or insulin and PA simultaneously for 15 minutes, before Western blotting was performed to assess the levels of phosphorylated and total p70 S6K. A representative blot from at least n = 3 independent biologic experiments per condition is shown.