This narrative review examines perimenopause as a critical transitional phase in women's lives, often accompanied by elevated vulnerability to anxiety and depression. Dysfunction of the gut-brain axis is one of the key factors contributing to perimenopausal mood disorders and is currently receiving extensive attention. GBA dysfunction can trigger neurotransmitter metabolic imbalance, intestinal barrier impairment, and neuroinflammatory responses. Tryptophan (Trp) and γ-aminobutyric acid (GABA) serve as essential precursors and direct modulators of key neurotransmitters, and the dysregulation of their metabolic pathways has been implicated in perimenopausal anxiety and depression in animal models and limited clinical observations. Trp influences 5-hydroxytryptamine (5-HT) by affecting emotional states. GABA is the primary inhibitory neurotransmitter in the central nervous system and is closely associated with anxiety and depression. Fluctuations in estrogen levels during perimenopause significantly alter the composition and metabolic activity of the gut microbiota, which in turn affects Trp metabolism and GABA synthesis through increased intestinal permeability, activation of immune-inflammatory responses, and disruption of hypothalamic-pituitary-adrenal (HPA) axis function. Although traditional hormone replacement therapy and pharmacological treatments are effective, they are associated with some side effects. Preliminary evidence from in vitro and animal studies suggests that nutritional interventions targeting Trp and GABA metabolism within the gut-brain axis may offer a novel research direction, though their efficacy in perimenopausal women remains to be established. Potential nutritional strategies, including supplementation with Trp and its precursors, inhibition of the kynurenine pathway (KP), and supplementation with probiotics and prebiotics, can modulate Trp and GABA metabolism. This review focuses on Trp and GABA metabolic regulation via the gut-brain axis to explore pathogenesis of perimenopausal anxiety and depression and summarize potential nutritional intervention targets, thereby providing a scientific basis for emotional management in perimenopausal women.
