Additionally, natural anti-inflammatory agents such as curcumin and fish oil have shown promising results in preclinical models of MDD, by decreasing nuclear factor-kappa B (NF-κB) signaling and TNF-α production (Lichtman et al., 2008; Eng et al., 2011; Smith et al., 2011; Burhani and Rasenick, 2017; Lopresti, 2017; Maki et al., 2018; Liu T. et al., 2019; Nerurkar et al., 2019). This evidence concerns the gene TNF and major depressive disorder.