Fig. 4.

Effects of an increased S1P turnover in insulin-secreting INS1E cells on cell viability, apoptosis, and ER stress after exposure to FFA. INS1E cells were incubated in the absence or presence of PA or OA (500 μM of each) for 24 h. Thereafter, (A) cell viability was measured by MTT assay, (B) activation of caspase-3 was detected by Western blot analysis of cleaved caspase-3 protein expression, and (C) induction of Chop was detected by Western blot analysis. Shown are representative WBs and a densitometry analysis of protein expression detected in all experiments. Shown are Means ± SEM from n = 3–6 independent experiments, each condition was measured in triplicates. ANOVA followed by Bonferroni. ∗P < 0.05, ∗∗P > 0.01, ∗∗∗P < 0.001 versus untreated, ###P < 0.001 versus INS1E-ctr cells treated in the same way.