Research Paper Volume 12, Issue 13 pp 13762—13790

Figure 5. Proinflammatory cytokines and DNA and protein modifications in relation to age and sex. Serum (A) and liver extracts (B–G) of adult (24 weeks) and old (109-114 weeks) male and female mice (n = 4-5) fed with a chow diet ad libitum were subjected to enzyme-linked immunosorbent assay (A), qRT-PCR analysis (B–D), tandem mass spectrometry (E, F), and immunoblotting (G). This way, proinflammatory cytokines (A–D), global DNA methylation (mdC/dC; E), and hydroxymethylation (hmdC/dC; F), as well as 3-nitrotyrosine (3-NT, G) protein modifications were determined. Hepatic transcription levels (B–D) were normalized by a composite factor based on the house-keeping genes Hprt and Rpl13a, whereas 3-NT-modified proteins were normalized to GAPDH (G). Except for (E) and (F), where data is given in %, data is presented as fold change compared to male adults (A–D, G). Statistical testing based on Two-Way ANOVA and post hoc analysis using Bonferroni’s test with * p < 0.05, ** p < 0.01 vs. adult and ^# p < 0.05, ^### p < 0.001 vs. male.