Moreover, EGCG can improve the depression symptoms in mice, and its mechanism may be related to reducing serum corticosterone levels, inhibiting the generation of malonaldehyde in the hippocampus, promoting the secretion of SOD and GSH-PX, and down-regulating the expressions of IDO, IL-6 mRNA and IL-1β mRNA [128]. The gene discussed is IL1B; the disease is major depressive disorder.