Figure 4. Significantly affected pathways founded using online software MetaboAnalyst 3.0 (p-value<0.05, impact>0.1). (A) Glyoxylate and dicarboxylate metabolism and Citrate cycle (TCA cycle) was significantly affected in young MDD patients; (B) Phenylalanine metabolism and Citrate cycle (TCA cycle) was significantly affected in middle-aged MDD patients.