PPARG and major depressive disorder: As the specific target of rosiglitazone, peroxisome proliferator-activated receptor γ (PPARγ) was found to be downregulated in the neurons of mice that exhibited depression-like behavior (Zhou et al., 2014), and PPARγ agonists (including rosiglitazone) were found to be effective antidepressants in both rodents and humans (Colle et al., 2017b).