FIG. 7.

High 4-HNE concentrations compromise β-cell survival. A: Rat islets and INS-1E cells were incubated for 48 or 24 h, respectively, with increasing concentrations of 4-HNE. Islets were pooled from three animals and divided into 10–12 islets per group. After incubation, islet cells were dispersed by mild trypsin digestion. Cell viability was determined at the end of the incubation by the trypan blue exclusion test. Cell viability in the absence of 4-HNE was >95% in both preparations. Results are mean ± SEM, n = 3. *P < 0.05 for the difference from untreated cells. B: INS-1E cells were taken for the FLICA apoptosis assay, as described in research design and methods. Results are mean ± SEM of the relative apoptotic levels in three different slides. C: Western blot analysis of 4-HNE–protein adducts in lysates prepared from INS-1E cells incubated for 48 h at 11 mmol/L glucose and the indicated concentrations of 4-HNE.