Abstract <p>This review examines the key pathways of bidirectional communication between the gut and brain along the microbiota–gut–brain axis, with particular emphasis on the effects of metabolites of lactic acid bacteria (metLABs) on neurons of the enteric and central nervous systems. Special attention is given to the role of metLABs in intracellular signaling. The review further explores the direct effects of metLABs on mitochondrial function in nervous tissue, neuronal plasticity, and neuritogenesis. Potential mechanisms for the release of neurotrophic factors in both cells and host organism following exposure to metLABs or probiotic products are analyzed. Although clinical evidence remains limited, existing studies suggest that regular consumption of metLAB-containing fermented foods may positively influence brain functions through modulation of the microbiota–gut–brain axis. At least two ongoing clinical trials currently investigate whether normalization of the gut microbiota through probiotic interventions can slow the progression of Alzheimer’s disease. As this field continues to advance rapidly, further studies are expected to provide important insights into the therapeutic potential of microbiota-targeted strategies for neurological health.</p>