In a phencyclidine-induced mouse model of schizophrenia, andrographolide blocked the interaction between NRF-2 and Keap1; reduced NRF-2 degradation; promoted the nuclear translocation of NRF-2; and reduced the levels of p-p65, p-IκBα, p-p38, and p-ERK1/2, which reduced the levels of prefrontal cortex proinflammatory cytokines, such as IL-1, TNF, IL-6, COX-2 and iNOS levels by activating the NRF-2 signalling pathway and inhibiting the MAPK and NF-kB signalling pathways to reduce inflammation, reduce oxidative stress, and improve schizophrenia-like behaviour (Wang et al., 2021b). The gene discussed is NOS2; the disease is schizophrenia.