Stimulation of brain function by ach and gaba producing lactobacillus - a gut microflora

The human gastrointestinal tract harbors a dynamically complex population of microorganisms, collectively termed the gut microbiota. Emerging evidence highlights its critical role in modulating the enteric nervous system (ENS) and central nervous system (CNS), thereby influencing the onset and progression of neurodegenerative disorders such as Alzheimer’s disease, anxiety, depression, and irritable bowel syndrome (IBS). Disruptions in microbial equilibrium contribute to these conditions through multiple communication pathways along the gut–brain axis (GBA), including immune modulation, vagus nerve signaling, and microbial regulation of neuroactive compounds. Notably, several gut microbes particularly from the genera Lactobacillus and Bifidobacterium have been identified as producers of mammalian neurotransmitters such as dopamine, γ-aminobutyric acid (GABA), serotonin, and acetylcholine (ACh). The probiotic potential of these microorganisms opens new avenues for therapeutic interventions. This review emphasizes the mechanisms of neurotransmitter production by Lactobacillus spp., with a focus on ACh and GABA, and explores their role in GBA-mediated communication and neurological health. • The gut–brain axis links intestinal microbes with central nervous system functions. • Lactobacillus spp. synthesize neurotransmitters such as acetylcholine and GABA. • Microbial neurotransmitters influence brain signaling via vagus nerve and immune pathways. • Probiotic Lactobacillus strains show potential in treating neurological disorders. • Future perspectives include engineered probiotics and personalized microbiome therapy.