XYS has a specific effect on regulating neurotransmitters such as dopamine, 5-hydroxytryptophan, and thyroid hormone; the latter plays an essential role in the pathogenesis of depression and anxiety (Kong et al., 2010; Ding et al., 2014; Zhang et al., 2021; Alkabban and Ferguson, 2023). Here, TG is linked to major depressive disorder.