Fig. 5.

Effect of dietary OTC supplementation on nSMase-2 mRNA levels in liver. Young and aged C57Bl6 mice were placed on either a 0.5% OTC or a SAA def. control diet for 4 weeks. Levels of nSMase-2 mRNA in the liver were assessed by quantitative RT-PCR (A, B) and real-time PCR (C). The levels of β-actin mRNA were used for normalization. Data are shown as mean values ± SD (n = 3–4). Statistical analyses were done according to two-way ANOVA and Bonferroni posttest analyses. The statistical significance of the main effect of diet and aging is shown by asterisks (*P < 0.05, **P < 0.01, and ***P < 0.001). No statistically significant interaction effects were present.