Figure 4: Comparison of cytokine levels (a) and cytokine and GSK-3 gene expression (b) in macrophages treated with phytohemagglutinin (PHA), lithium (Li), xanthine-catechin (XC) mixture, and Li and XC mixture (LXC) and incubated for 72 h. Gene expression in all the samples was normalized to that of the housekeeping gene β-actin and is expressed as fold change compared with that in control cells. Statistical analysis was performed using two-way analysis of variance followed by the Bonferroni post hoc test. The different letters (i.e., A, B, C, and D) indicate statistical differences in each treatment at .