Si-Ni-San reduces the release of inflammatory factors IL-1β, IL-6, IL-2, and TNF-α in the peripheral fluid of patients with post-stroke depression and regulates the over-activation of the HPA axis, thereby exerting an antidepressant effect (Guo et al., 2009; Li et al., 2013). The gene discussed is IL1B; the disease is major depressive disorder.