Modulatory Effects of Phytochemicals on Gut-Brain Axis: Therapeutic Implication

Abstract

This article explores the potential therapeutic implications of phytochemicals on the gut-brain axis (GBA), which serves as a communication network between the central nervous system and the enteric nervous system. Phytochemicals, which are compounds derived from plants, have been shown to interact with the gut microbiota, immune system, and neurotransmitter systems, thereby influencing brain function. Phytochemicals such as polyphenols, carotenoids, flavonoids, and terpenoids have been identified as having potential therapeutic implications for various neurological disorders. The GBA plays a critical role in the development and progression of various neurological disorders, including Parkinson's disease, multiple sclerosis, depression, anxiety, and autism spectrum disorders. Dysbiosis, or an imbalance in gut microbiota composition, has been associated with a range of neurological disorders, suggesting that modulating the gut microbiota may have potential therapeutic implications for these conditions. Although these findings are promising, further research is needed to elucidate the optimal use of phytochemicals in neurological disorder treatment, as well as their potential interactions with other medications. The literature review search was conducted using predefined search terms such as phytochemicals, gut-brain axis, neurodegenerative, and Parkinson in PubMed, Embase, and the Cochrane library.

Keywords: Centeral nervous system; medicinal plants; microbiota; neurodegeneration; polyphenol.

FIGURE 1

Modulatory effects of phytochemicals on the gut–brain axis. Abbreviations: Aβ, amyloid beta. BDNF, brain-derived neurotrophic factor; EGCG, epigallocatechin-3-gallate; GABA, γ-aminobutyric acid; HPA, hypothalamic-pituitary-adrenal; IL, interleukin; MPTP, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine; MDA, malondialdehyde; NF-κB, nuclear factor kappa B; NLRP3, NLR family pyrin domain containing 3; TLR4, Toll-like receptor; TNF, tumor necrosis factor alpha; 6-OHDA, 6-hydroxydopamine.

FIGURE 2

Classification of dietary phytochemicals.