PDHB and major depressive disorder: Seven DE-CRGs were identified at the intersection of IBD and MDD using a Venn diagram (Figure 1H), including the following: DLD (downregulated in both IBD and MDD), DLAT (downregulated in both IBD and MDD), DLST (upregulated in both IBD and MDD), NLRP3 (upregulated in IBD, downregulated in MDD), PDHB (downregulated in both IBD and MDD), DBT (downregulated in both IBD and MDD), and NFE2L2 (downregulated in IBD, upregulated in MDD).