IL6 and major depressive disorder: The quantification of the pro-inflammatory cytokine IL-6 in the cell culture media of primary isolated astrocytes after 1, 3, and 7 days post in vitro isolation show that luteolin treatment didn’t affect the IL-6 level in PBS mice (PBS + L vs. PBS group), while LPS treatment significantly increase the production of IL-6 by astrocytes (LPS vs. PBS group), and luteolin treatment significantly decreased this pro-inflammatory cytokine secretion by astrocytes in LPS-induced depression mice (LPS + L vs. LPS group) (Figure 3D).