HTR5A and insomnia: Several experimental studies have preliminarily confirmed that Banxia-Yiyiren may improve sleep by regulating the expression of serum inflammatory factors and the hippocampal neurotransmitters orexin and 5-HT and their receptors (Wang Liang et al., 2022); however, the specific pathway by which Banxia-Yiyiren regulates the gut microbiota and its metabolites in insomnia models is still unclear.