Plant-Derived Nutraceuticals in Mental Health and Brain Function: Mechanisms of Action and Therapeutic Potential

Considering the multiple benefits of nutraceuticals, and given the growing interest in exploring these effects, understanding their mechanisms and implications in mental well-being and neurological integrity is essential and requires further examination to clarify their therapeutic potential. This narrative review provides a comprehensive overview of recent advances in plant-derived nutraceuticals, particularly regarding their impact on mental health and brain function, by examining their bioactive components, their involvement in neuropsychiatric conditions, their role in neurodegeneration, emerging nutraceuticals with clinical relevance, and gut microbiome interactions with nutraceuticals and phytochemicals. Essential fatty acids, prebiotics, phytochemicals, and nutrients such as amino acids, vitamins, minerals, and omega-3 fatty acids contribute to mood regulation and cognitive function. Nutraceuticals can prevent or slow neurodegeneration by targeting misfolded proteins and modulating oxidative stress, neuroinflammation, mitochondrial dysfunction, and dysregulated signaling pathways. Phytochemicals act as phytopsychobiotics, influencing mental health through gut microbiome modulation and generation of bioactive metabolites. Hypericum and curcumin exert neuroprotective, anti-inflammatory, antioxidant, and antidepressant effects. Ginsenosides promote neuroprotection, partially via gut microbiome-mediated mechanisms. Administration of Ginkgo biloba polysaccharides and lavender essential oil improves neurotransmitter regulation, intestinal barrier integrity, and depressive-like behaviors in preclinical models. Omega-3 polyunsaturated fatty acids, anthocyanins, quercetin, catechins, and chlorogenic acid support neuroprotection and cognitive function via modulation of beneficial gut bacteria, short-chain fatty acid production, anti-inflammatory effects, and serotonin metabolism. The landscape of nutraceuticals offers a diverse range of dietary options with considerable potential to promote mental health and prevent neurodegeneration, but further research is required to elucidate how the gut microbiome may enhance these bioactivities.