HTR4 and major depressive disorder: We found a number of genes associated with psychiatric disorders showed altered expression under CJL (Figures 2–6), including several serotonin receptors htr2a, htr4, htr7, htr5b, htr6, and htr3a. These genes have been found to be involved in depression-related processes (Serretti et al., 2007; Lohoff et al., 2011; Nautiyal and Hen, 2017).