Fecal microbiota transplantation (FMT) has emerged as a key tool to explore the role of the microbiome-gut-brain axis in psychiatric disorders. However, the field is hindered by significant methodological inconsistencies. A comprehensive literature search identified 31 studies performing FMT from human patients with psychiatric conditions into rodent models. None of the 31 studies followed an identical FMT protocol. Significant heterogeneity was observed across studies in rodent model selection, including germ-free, antibiotic-pretreated, or specific pathogen-free approaches, in antibiotic regimens, timing and microbiota depletion verification, as well as in FMT donor strategy, dosage, frequency, engraftment assessment, and behavioral testing schedules. This review highlights the necessity for standardized methodologies in microbiome research. Evidence-based recommendations are provided to promote reproducibility in future work. Investigators are encouraged to publish transparent and rigorous protocols, to enhance the translational potential of microbiome-gut-brain axis research.
D’Onofrio et al. (Thu,) studied this question.