CXCL8 and major depressive disorder: The previous study established a relatively precise effect of the Chinese Angelica Decoction for Replenishing Blood (Danggui-Buxue decoction, DBD) on DM with depression (Wang et al., 2018), and investigation of the mechanisms showed that DBD reduces serum levels of inflammatory factors such as TNF-α, CRP, IL-6, and IL-8, thereby inhibiting the systemic inflammatory response and achieving the positive regulation of DM complicated with depression (Wang et al., 2020a) (Table 1; Figure 1).